Version to make it easier to reuse without source modifications

Files at this revision

API Documentation at this revision

Comitter:
JMF
Date:
Tue Mar 27 17:26:35 2018 +0000
Commit message:
Initial commit

Changed in this revision

MQTT.h Show annotated file Show diff for this revision Revisions of this file
MQTTAsync.h Show annotated file Show diff for this revision Revisions of this file
MQTTClient.h Show annotated file Show diff for this revision Revisions of this file
MQTTLogging.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTConnect.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTConnectClient.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTConnectServer.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTDeserializePublish.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTFormat.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTFormat.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTPacket.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTPacket.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTPublish.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTSerializePublish.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTSubscribe.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTSubscribeClient.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTSubscribeServer.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTUnsubscribe.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTUnsubscribeClient.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/MQTTUnsubscribeServer.c Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/StackTrace.h Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/samples/publish-subscribe.txt Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/samples/simple-publish.txt Show annotated file Show diff for this revision Revisions of this file
MQTTPacket/test/test1.txt Show annotated file Show diff for this revision Revisions of this file
MQTTSocket.h Show annotated file Show diff for this revision Revisions of this file
MQTTmbed.h Show annotated file Show diff for this revision Revisions of this file
README.md Show annotated file Show diff for this revision Revisions of this file
mbed_lib.json Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 5cd4781e0c88 MQTT.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTT.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,46 @@
+#ifndef __MQTT_H__
+#define __MQTT_H__
+
+#include "MQTTmbed.h"
+#include "MQTTSocket.h"
+
+template <class T>
+class MQTTconnect : public MQTTSocket
+{
+    T eth;
+  public:
+    MQTTconnect() : MQTTSocket(&eth)
+    { eth.connect(); }
+
+    T& getEth()
+    { return eth; }
+};
+
+//
+// To add additional transports, Define it as:
+//
+#define MQTT_BG96         100
+#define MQTT_WNC14A2A     101
+#define MQTT_ETHERNET     102
+
+//
+// Then define the interface that will be used:
+//
+#if   MBED_CONF_APP_MQTT_INTERFACE == MQTT_BG96
+#define _ift BG96Interface
+
+#elif MBED_CONF_APP_MQTT_INTERFACE == MQTT_WNC14A2A
+#define _ift WNC14A2AInterface
+
+#elif MBED_CONF_APP_MQTT_INTERFACE == MQTT_ETHERNET
+#define _ift EthernetInterface
+
+#else
+#error "No MQTT Network Transport chosen. Please add 'config.mqtt-interfaces.value' to your mbed_app.json (see README.md for more information)."
+#endif
+
+typedef MQTTconnect<_ift> MQTTct; 
+typedef _ift MQTTnet;
+
+#endif
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTAsync.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTAsync.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,606 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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(MQTTASYNC_H)
+#define MQTTASYNC_H
+
+#include "MQTTPacket.h"
+#include "stdio.h"
+
+namespace MQTT
+{
+
+
+enum QoS { QOS0, QOS1, QOS2 };
+
+
+struct Message
+{
+    enum QoS qos;
+    bool retained;
+    bool dup;
+    unsigned short id;
+    void *payload;
+    size_t payloadlen;
+};
+
+
+class PacketId
+{
+public:
+    PacketId();
+    
+    int getNext();
+   
+private:
+    static const int MAX_PACKET_ID = 65535;
+    int next;
+};
+
+typedef void (*messageHandler)(Message*);
+
+typedef struct limits
+{
+	int MAX_MQTT_PACKET_SIZE; // 
+	int MAX_MESSAGE_HANDLERS;  // each subscription requires a message handler
+	int MAX_CONCURRENT_OPERATIONS;  // each command which runs concurrently can have a result handler, when we are in multi-threaded mode
+	int command_timeout_ms;
+		
+	limits()
+	{
+		MAX_MQTT_PACKET_SIZE = 100;
+		MAX_MESSAGE_HANDLERS = 5;
+		MAX_CONCURRENT_OPERATIONS = 1; // 1 indicates single-threaded mode - set to >1 for multithreaded mode
+		command_timeout_ms = 30000;
+	}
+} Limits;
+  
+
+/**
+ * @class Async
+ * @brief non-blocking, threaded MQTT client API
+ * @param Network a network class which supports send, receive
+ * @param Timer a timer class with the methods: 
+ */ 
+template<class Network, class Timer, class Thread, class Mutex> class Async
+{
+    
+public:    
+
+	struct Result
+	{
+    	/* success or failure result data */
+    	Async<Network, Timer, Thread, Mutex>* client;
+		int rc;
+	};
+
+	typedef void (*resultHandler)(Result*);	
+   
+    Async(Network* network, const Limits limits = Limits()); 
+        
+    typedef struct
+    {
+        Async* client;
+        Network* network;
+    } connectionLostInfo;
+    
+    typedef int (*connectionLostHandlers)(connectionLostInfo*);
+    
+    /** Set the connection lost callback - called whenever the connection is lost and we should be connected
+     *  @param clh - pointer to the callback function
+     */
+    void setConnectionLostHandler(connectionLostHandlers clh)
+    {
+        connectionLostHandler.attach(clh);
+    }
+    
+    /** 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);
+    }
+           
+    int connect(resultHandler fn, MQTTPacket_connectData* options = 0);
+    
+     template<class T>
+    int connect(void(T::*method)(Result *), MQTTPacket_connectData* options = 0, T *item = 0);  // alternative to pass in pointer to member function
+        
+    int publish(resultHandler rh, const char* topic, Message* message);
+    
+    int subscribe(resultHandler rh, const char* topicFilter, enum QoS qos, messageHandler mh);
+    
+    int unsubscribe(resultHandler rh, const char* topicFilter);
+    
+    int disconnect(resultHandler rh);
+    
+private:
+
+    void run(void const *argument);
+    int cycle(int timeout);
+    int waitfor(int packet_type, Timer& atimer);
+	int keepalive();
+	int findFreeOperation();
+
+    int decodePacket(int* value, int timeout);
+    int readPacket(int timeout);
+    int sendPacket(int length, int timeout);
+	int deliverMessage(MQTTString* topic, Message* message);
+    
+    Thread* thread;
+    Network* ipstack;
+    
+    Limits limits;
+    
+    char* buf;  
+    char* readbuf;
+
+    Timer ping_timer, connect_timer;
+    unsigned int keepAliveInterval;
+	bool ping_outstanding;
+    
+    PacketId packetid;
+    
+    typedef Callback<void(Result*)> resultHandlerFP;    
+    resultHandlerFP connectHandler; 
+    
+    typedef Callback<void(Message*)> messageHandlerFP;
+    struct MessageHandlers
+    {
+    	const char* topic;
+    	messageHandlerFP fp;
+    } *messageHandlers;      // Message handlers are indexed by subscription topic
+    
+    // how many concurrent operations should we allow?  Each one will require a function pointer
+    struct Operations
+    {
+    	unsigned short id;
+    	resultHandlerFP fp;
+    	const char* topic;         // if this is a publish, store topic name in case republishing is required
+    	Message* message;    // for publish, 
+    	Timer timer;         // to check if the command has timed out
+    } *operations;           // result handlers are indexed by packet ids
+
+	static void threadfn(void* arg);
+	
+	messageHandlerFP defaultMessageHandler;
+    
+    typedef Callback<int(connectionLostInfo*)> connectionLostFP;
+    
+    connectionLostFP connectionLostHandler;
+    
+};
+
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> void MQTT::Async<Network, Timer, Thread, Mutex>::threadfn(void* arg)
+{
+    ((Async<Network, Timer, Thread, Mutex>*) arg)->run(NULL);
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> MQTT::Async<Network, Timer, Thread, Mutex>::Async(Network* network, Limits limits)  : limits(limits), packetid()
+{
+	this->thread = 0;
+	this->ipstack = network;
+	this->ping_timer = Timer();
+	this->ping_outstanding = 0;
+	   
+	// How to make these memory allocations portable?  I was hoping to avoid the heap
+	buf = new char[limits.MAX_MQTT_PACKET_SIZE];
+	readbuf = new char[limits.MAX_MQTT_PACKET_SIZE];
+	this->operations = new struct Operations[limits.MAX_CONCURRENT_OPERATIONS];
+	for (int i = 0; i < limits.MAX_CONCURRENT_OPERATIONS; ++i)
+		operations[i].id = 0;
+	this->messageHandlers = new struct MessageHandlers[limits.MAX_MESSAGE_HANDLERS];
+	for (int i = 0; i < limits.MAX_MESSAGE_HANDLERS; ++i)
+		messageHandlers[i].topic = 0;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::sendPacket(int length, int timeout)
+{
+    int sent = 0;
+    
+    while (sent < length)
+        sent += ipstack->write(&buf[sent], length, timeout);
+	if (sent == length)
+	    ping_timer.countdown(this->keepAliveInterval); // record the fact that we have successfully sent the packet    
+    return sent;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::decodePacket(int* value, int timeout)
+{
+    char c;
+    int multiplier = 1;
+    int len = 0;
+	const int MAX_NO_OF_REMAINING_LENGTH_BYTES = 4;
+
+    *value = 0;
+    do
+    {
+        int rc = MQTTPACKET_READ_ERROR;
+
+        if (++len > MAX_NO_OF_REMAINING_LENGTH_BYTES)
+        {
+            rc = MQTTPACKET_READ_ERROR; /* bad data */
+            goto exit;
+        }
+        rc = ipstack->read(&c, 1, timeout);
+        if (rc != 1)
+            goto exit;
+        *value += (c & 127) * multiplier;
+        multiplier *= 128;
+    } while ((c & 128) != 0);
+exit:
+    return len;
+}
+
+
+/**
+ * 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, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::readPacket(int timeout) 
+{
+    int rc = -1;
+    MQTTHeader header = {0};
+    int len = 0;
+    int rem_len = 0;
+
+    /* 1. read the header byte.  This has the packet type in it */
+    if (ipstack->read(readbuf, 1, timeout) != 1)
+        goto exit;
+
+    len = 1;
+    /* 2. read the remaining length.  This is variable in itself */
+    decodePacket(&rem_len, timeout);
+    len += MQTTPacket_encode(readbuf + 1, rem_len); /* put the original remaining length back into the buffer */
+
+    /* 3. read the rest of the buffer using a callback to supply the rest of the data */
+    if (ipstack->read(readbuf + len, rem_len, timeout) != rem_len)
+        goto exit;
+
+    header.byte = readbuf[0];
+    rc = header.bits.type;
+exit:
+    return rc;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::deliverMessage(MQTTString* topic, Message* message)
+{
+	int rc = -1;
+
+	// we have to find the right message handler - indexed by topic
+	for (int i = 0; i < limits.MAX_MESSAGE_HANDLERS; ++i)
+	{
+		if (messageHandlers[i].topic != 0 && MQTTPacket_equals(topic, (char*)messageHandlers[i].topic))
+		{
+			messageHandlers[i].fp(message);
+			rc = 0;
+			break;
+		}
+	}
+	
+	return rc;
+}
+
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::cycle(int timeout)
+{
+    /* get one piece of work off the wire and one pass through */
+
+    // read the socket, see what work is due
+    int packet_type = readPacket(timeout);
+    
+	int len, rc;
+    switch (packet_type)
+    {
+        case CONNACK:
+			if (this->thread)
+			{
+				Result res = {this, 0};
+            	if (MQTTDeserialize_connack(&res.rc, readbuf, limits.MAX_MQTT_PACKET_SIZE) == 1)
+                	;
+				connectHandler(&res);
+				connectHandler.detach(); // only invoke the callback once
+			}
+			break;
+        case PUBACK:
+        	if (this->thread)
+        		; //call resultHandler
+        case SUBACK:
+            break;
+        case PUBLISH:
+			MQTTString topicName;
+			Message msg;
+			rc = MQTTDeserialize_publish((int*)&msg.dup, (int*)&msg.qos, (int*)&msg.retained, (int*)&msg.id, &topicName,
+								 (char**)&msg.payload, (int*)&msg.payloadlen, readbuf, limits.MAX_MQTT_PACKET_SIZE);;
+			if (msg.qos == QOS0)
+				deliverMessage(&topicName, &msg);
+            break;
+        case PUBREC:
+   	        int type, dup, mypacketid;
+   	        if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, limits.MAX_MQTT_PACKET_SIZE) == 1)
+   	            ; 
+   	        // must lock this access against the application thread, if we are multi-threaded
+			len = MQTTSerialize_ack(buf, limits.MAX_MQTT_PACKET_SIZE, PUBREL, 0, mypacketid);
+		    rc = sendPacket(len, timeout); // send the PUBREL packet
+			if (rc != len) 
+				goto exit; // there was a problem
+
+            break;
+        case PUBCOMP:
+            break;
+        case PINGRESP:
+			ping_outstanding = false;
+            break;
+    }
+	keepalive();
+exit:
+    return packet_type;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::keepalive()
+{
+	int rc = 0;
+
+	if (keepAliveInterval == 0)
+		goto exit;
+
+	if (ping_timer.expired())
+	{
+		if (ping_outstanding)
+			rc = -1;
+		else
+		{
+			int len = MQTTSerialize_pingreq(buf, limits.MAX_MQTT_PACKET_SIZE);
+			rc = sendPacket(len, 1000); // send the ping packet
+			if (rc != len) 
+				rc = -1; // indicate there's a problem
+			else
+				ping_outstanding = true;
+		}
+	}
+
+exit:
+	return rc;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> void MQTT::Async<Network, Timer, Thread, Mutex>::run(void const *argument)
+{
+	while (true)
+		cycle(ping_timer.left_ms());
+}
+
+
+// only used in single-threaded mode where one command at a time is in process
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::waitfor(int packet_type, Timer& atimer)
+{
+	int rc = -1;
+	
+	do
+    {
+		if (atimer.expired()) 
+			break; // we timed out
+	}
+	while ((rc = cycle(atimer.left_ms())) != packet_type);	
+	
+	return rc;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::connect(resultHandler resultHandler, MQTTPacket_connectData* options)
+{
+	connect_timer.countdown(limits.command_timeout_ms);
+
+    MQTTPacket_connectData default_options = MQTTPacket_connectData_initializer;
+    if (options == 0)
+        options = &default_options; // set default options if none were supplied
+    
+    this->keepAliveInterval = options->keepAliveInterval;
+	ping_timer.countdown(this->keepAliveInterval);
+    int len = MQTTSerialize_connect(buf, limits.MAX_MQTT_PACKET_SIZE, options);
+    int rc = sendPacket(len, connect_timer.left_ms()); // send the connect packet
+	if (rc != len) 
+		goto exit; // there was a problem
+    
+    if (resultHandler == 0)     // wait until the connack is received 
+    {
+        // this will be a blocking call, wait for the connack
+		if (waitfor(CONNACK, connect_timer) == CONNACK)
+		{
+        	int connack_rc = -1;
+        	if (MQTTDeserialize_connack(&connack_rc, readbuf, limits.MAX_MQTT_PACKET_SIZE) == 1)
+	        	rc = connack_rc;
+	    }
+    }
+    else
+    {
+        // set connect response callback function
+        connectHandler.attach(resultHandler);
+        
+        // start background thread            
+        this->thread = new Thread((void (*)(void const *argument))&MQTT::Async<Network, Timer, Thread, Mutex>::threadfn, (void*)this);
+    }
+    
+exit:
+    return rc;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::findFreeOperation()
+{
+	int found = -1;
+	for (int i = 0; i < limits.MAX_CONCURRENT_OPERATIONS; ++i)
+	{
+		if (operations[i].id == 0)
+		{
+			found = i;
+			break;
+		}
+	}
+	return found;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::subscribe(resultHandler resultHandler, const char* topicFilter, enum QoS qos, messageHandler messageHandler)
+{
+	int index = 0;
+	if (this->thread)
+		index = findFreeOperation();	
+	Timer& atimer = operations[index].timer;
+	
+	atimer.countdown(limits.command_timeout_ms);
+    MQTTString topic = {(char*)topicFilter, 0, 0};
+    
+    int len = MQTTSerialize_subscribe(buf, limits.MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic, (int*)&qos);
+    int rc = sendPacket(len, atimer.left_ms()); // send the subscribe packet
+	if (rc != len) 
+		goto exit; // there was a problem
+    
+    /* wait for suback */
+    if (resultHandler == 0)
+    {
+        // this will block
+        if (waitfor(SUBACK, atimer) == SUBACK)
+        {
+            int count = 0, grantedQoS = -1, mypacketid;
+            if (MQTTDeserialize_suback(&mypacketid, 1, &count, &grantedQoS, readbuf, limits.MAX_MQTT_PACKET_SIZE) == 1)
+                rc = grantedQoS; // 0, 1, 2 or 0x80 
+            if (rc != 0x80)
+            {
+            	for (int i = 0; i < limits.MAX_MESSAGE_HANDLERS; ++i)
+				{
+					if (messageHandlers[i].topic == 0)
+					{
+						messageHandlers[i].topic = topicFilter;
+						messageHandlers[i].fp.attach(messageHandler);
+						rc = 0;
+						break;
+					}
+				}
+            }
+        }
+    }
+    else
+    {
+        // set subscribe response callback function
+        
+    }
+    
+exit:
+    return rc;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::unsubscribe(resultHandler resultHandler, const char* topicFilter)
+{
+	int index = 0;
+	if (this->thread)
+		index = findFreeOperation();	
+	Timer& atimer = operations[index].timer;
+
+	atimer.countdown(limits.command_timeout_ms);
+    MQTTString topic = {(char*)topicFilter, 0, 0};
+    
+    int len = MQTTSerialize_unsubscribe(buf, limits.MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic);
+    int rc = sendPacket(len, atimer.left_ms()); // send the subscribe packet
+	if (rc != len) 
+		goto exit; // there was a problem
+    
+    // set unsubscribe response callback function
+        
+    
+exit:
+    return rc;
+}
+
+
+   
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::publish(resultHandler resultHandler, const char* topicName, Message* message)
+{
+	int index = 0;
+	if (this->thread)
+		index = findFreeOperation();	
+	Timer& atimer = operations[index].timer;
+
+	atimer.countdown(limits.command_timeout_ms);
+    MQTTString topic = {(char*)topicName, 0, 0};
+
+	if (message->qos == QOS1 || message->qos == QOS2)
+		message->id = packetid.getNext();
+    
+	int len = MQTTSerialize_publish(buf, limits.MAX_MQTT_PACKET_SIZE, 0, message->qos, message->retained, message->id, topic, (char*)message->payload, message->payloadlen);
+    int rc = sendPacket(len, atimer.left_ms()); // send the subscribe packet
+	if (rc != len) 
+		goto exit; // there was a problem
+    
+    /* wait for acks */
+    if (resultHandler == 0)
+    {
+ 		if (message->qos == QOS1)
+		{
+	        if (waitfor(PUBACK, atimer) == PUBACK)
+    	    {
+    	        int type, dup, mypacketid;
+    	        if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, limits.MAX_MQTT_PACKET_SIZE) == 1)
+    	            rc = 0; 
+    	    }
+		}
+		else if (message->qos == QOS2)
+		{
+	        if (waitfor(PUBCOMP, atimer) == PUBCOMP)
+	   	    {
+	   	    	int type, dup, mypacketid;
+            	if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, limits.MAX_MQTT_PACKET_SIZE) == 1)
+    	           	rc = 0; 
+			}
+
+		}
+    }
+    else
+    {
+        // set publish response callback function
+        
+    }
+    
+exit:
+    return rc;
+}
+
+
+template<class Network, class Timer, class Thread, class Mutex> int MQTT::Async<Network, Timer, Thread, Mutex>::disconnect(resultHandler resultHandler)
+{  
+    Timer timer = Timer(limits.command_timeout_ms);     // we might wait for incomplete incoming publishes to complete
+    int len = MQTTSerialize_disconnect(buf, limits.MAX_MQTT_PACKET_SIZE);
+    int rc = sendPacket(len, timer.left_ms());   // send the disconnect packet
+    
+    return (rc == len) ? 0 : -1;
+}
+
+
+
+#endif
diff -r 000000000000 -r 5cd4781e0c88 MQTTClient.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTClient.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,1050 @@
+/*******************************************************************************
+ * Copyright (c) 2014, 2017 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
+ *    Ian Craggs - fix for bug 458512 - QoS 2 messages
+ *    Ian Craggs - fix for bug 460389 - send loop uses wrong length
+ *    Ian Craggs - fix for bug 464169 - clearing subscriptions
+ *    Ian Craggs - fix for bug 464551 - enums and ints can be different size
+ *    Mark Sonnentag - fix for bug 475204 - inefficient instantiation of Timer
+ *    Ian Craggs - fix for bug 475749 - packetid modified twice
+ *    Ian Craggs - add ability to set message handler separately #6
+ *******************************************************************************/
+
+#if !defined(MQTTCLIENT_H)
+#define MQTTCLIENT_H
+
+#include "MQTTPacket.h"
+#include <stdio.h>
+#include "MQTTLogging.h"
+
+#if !defined(MQTTCLIENT_QOS1)
+    #define MQTTCLIENT_QOS1 1
+#endif
+#if !defined(MQTTCLIENT_QOS2)
+    #define MQTTCLIENT_QOS2 0
+#endif
+
+namespace MQTT
+{
+
+
+enum QoS { QOS0, QOS1, QOS2 };
+
+// all failure return codes must be negative
+enum returnCode { 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(MQTTString &aTopicName, struct Message &aMessage)  : message(aMessage), topicName(aTopicName)
+    { }
+
+    struct Message &message;
+    MQTTString &topicName;
+};
+
+
+struct connackData
+{
+    int rc;
+    bool sessionPresent;
+};
+
+
+struct subackData
+{
+    int grantedQoS;
+};
+
+
+class PacketId
+{
+public:
+    PacketId()
+    {
+        next = 0;
+    }
+
+    int getNext()
+    {
+        return next = (next == MAX_PACKET_ID) ? 1 : next + 1;
+    }
+
+private:
+    static const int MAX_PACKET_ID = 65535;
+    int next;
+};
+
+
+/**
+ * @class Client
+ * @brief blocking, non-threaded MQTT 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_MQTT_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.  Set to 0 to remove.
+     */
+    void setDefaultMessageHandler(messageHandler mh)
+    {
+        if (mh != 0)
+            defaultMessageHandler=mh;
+        else
+            defaultMessageHandler=NULL;
+    }
+
+    /** Set a message handling callback.  This can be used outside of the the subscribe method.
+     *  @param topicFilter - a topic pattern which can include wildcards
+     *  @param mh - pointer to the callback function. If 0, removes the callback if any
+     */
+    int setMessageHandler(const char* topicFilter, messageHandler 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(MQTTPacket_connectData& options);
+
+    /** 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
+     *  @param connackData - connack data to be returned
+     *  @return success code -
+     */
+    int connect(MQTTPacket_connectData& options, connackData& data);
+
+    /** 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(const char* topicName, 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(const char* topicName, 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(const char* topicName, 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(const char* topicFilter, enum QoS qos, messageHandler mh);
+
+    /** 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
+     *  @param
+     *  @return success code -
+     */
+    int subscribe(const char* topicFilter, enum QoS qos, messageHandler mh, subackData &data);
+
+    /** 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(const char* topicFilter);
+
+    /** MQTT Disconnect - send an MQTT disconnect packet, and clean up any state
+     *  @return success code -
+     */
+    int disconnect();
+
+    /** 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;
+    }
+
+private:
+
+    void closeSession();
+    void cleanSession();
+    int cycle(Timer& timer);
+    int waitfor(int packet_type, Timer& timer);
+    int keepalive();
+    int publish(int len, Timer& timer, enum QoS qos);
+
+    int decodePacket(int* value, int timeout);
+    int readPacket(Timer& timer);
+    int sendPacket(int length, Timer& timer);
+    int deliverMessage(MQTTString& topicName, Message& message);
+    bool isTopicMatched(char* topicFilter, MQTTString& topicName);
+
+    Network& ipstack;
+    unsigned long command_timeout_ms;
+
+    unsigned char sendbuf[MAX_MQTT_PACKET_SIZE];
+    unsigned char readbuf[MAX_MQTT_PACKET_SIZE];
+
+    Timer last_sent, last_received;
+    unsigned int keepAliveInterval;
+    bool ping_outstanding;
+    bool cleansession;
+
+    PacketId packetid;
+
+    struct MessageHandlers
+    {
+        const char* topicFilter;
+        Callback<void( MessageData&)> fp;
+    } messageHandlers[MAX_MESSAGE_HANDLERS];      // Message handlers are indexed by subscription topic
+
+    Callback<void(MessageData&)> defaultMessageHandler;
+
+    bool isconnected;
+
+#if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
+    unsigned char pubbuf[MAX_MQTT_PACKET_SIZE];  // store the last publish for sending on reconnect
+    int inflightLen;
+    unsigned short inflightMsgid;
+    enum QoS inflightQoS;
+#endif
+
+#if MQTTCLIENT_QOS2
+    bool pubrel;
+    #if !defined(MAX_INCOMING_QOS2_MESSAGES)
+        #define MAX_INCOMING_QOS2_MESSAGES 10
+    #endif
+    unsigned short incomingQoS2messages[MAX_INCOMING_QOS2_MESSAGES];
+    bool isQoS2msgidFree(unsigned short id);
+    bool useQoS2msgid(unsigned short id);
+    void freeQoS2msgid(unsigned short id);
+#endif
+
+};
+
+}
+
+
+template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
+void MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::cleanSession()
+{
+    for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+        messageHandlers[i].topicFilter = 0;
+
+#if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
+    inflightMsgid = 0;
+    inflightQoS = QOS0;
+#endif
+
+#if MQTTCLIENT_QOS2
+    pubrel = false;
+    for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
+        incomingQoS2messages[i] = 0;
+#endif
+}
+
+
+template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
+void MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::closeSession()
+{
+    ping_outstanding = false;
+    isconnected = false;
+    if (cleansession)
+        cleanSession();
+}
+
+
+template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
+MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::Client(Network& network, unsigned int command_timeout_ms)  : ipstack(network), packetid()
+{
+    this->command_timeout_ms = command_timeout_ms;
+    cleansession = true;
+      closeSession();
+}
+
+
+#if MQTTCLIENT_QOS2
+template<class Network, class Timer, int a, int b>
+bool MQTT::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 MQTT::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;
+}
+
+
+template<class Network, class Timer, int a, int b>
+void MQTT::Client<Network, Timer, a, b>::freeQoS2msgid(unsigned short id)
+{
+    for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
+    {
+        if (incomingQoS2messages[i] == id)
+        {
+            incomingQoS2messages[i] = 0;
+            return;
+        }
+    }
+}
+#endif
+
+
+template<class Network, class Timer, int a, int b>
+int MQTT::Client<Network, Timer, a, b>::sendPacket(int length, Timer& timer)
+{
+    int rc = FAILURE,
+        sent = 0;
+
+    while (sent < length)
+    {
+        rc = ipstack.write(&sendbuf[sent], length - sent, timer.left_ms());
+        if (rc < 0)  // there was an error writing the data
+            break;
+        sent += rc;
+        if (timer.expired()) // only check expiry after at least one attempt to write
+            break;
+    }
+    if (sent == length)
+    {
+        if (this->keepAliveInterval > 0)
+            last_sent.countdown(this->keepAliveInterval); // record the fact that we have successfully sent the packet
+        rc = SUCCESS;
+    }
+    else
+        rc = FAILURE;
+
+#if defined(MQTT_DEBUG)
+    char printbuf[150];
+    DEBUG("Rc %d from sending packet %s\r\n", rc, 
+        MQTTFormat_toServerString(printbuf, sizeof(printbuf), sendbuf, length));
+#endif
+    return rc;
+}
+
+
+template<class Network, class Timer, int a, int b>
+int MQTT::Client<Network, Timer, a, b>::decodePacket(int* value, int timeout)
+{
+    unsigned char c;
+    int multiplier = 1;
+    int len = 0;
+    const int MAX_NO_OF_REMAINING_LENGTH_BYTES = 4;
+
+    *value = 0;
+    do
+    {
+        int rc = MQTTPACKET_READ_ERROR;
+
+        if (++len > MAX_NO_OF_REMAINING_LENGTH_BYTES)
+        {
+            rc = MQTTPACKET_READ_ERROR; /* bad data */
+            goto exit;
+        }
+        rc = ipstack.read(&c, 1, timeout);
+        if (rc != 1)
+            goto exit;
+        *value += (c & 127) * multiplier;
+        multiplier *= 128;
+    } while ((c & 128) != 0);
+exit:
+    return len;
+}
+
+
+/**
+ * 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, 0 if none, -1 if error
+ */
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::readPacket(Timer& timer)
+{
+    int rc = FAILURE;
+    MQTTHeader header = {0};
+    int len = 0;
+    int rem_len = 0;
+
+    /* 1. read the header byte.  This has the packet type in it */
+    rc = ipstack.read(readbuf, 1, timer.left_ms());
+    if (rc != 1)
+        goto exit;
+
+    len = 1;
+    /* 2. read the remaining length.  This is variable in itself */
+    decodePacket(&rem_len, timer.left_ms());
+    len += MQTTPacket_encode(readbuf + 1, rem_len); /* put the original remaining length into the buffer */
+
+    if (rem_len > (MAX_MQTT_PACKET_SIZE - len))
+    {
+        rc = BUFFER_OVERFLOW;
+        goto exit;
+    }
+
+    /* 3. read the rest of the buffer using a callback to supply the rest of the data */
+    if (rem_len > 0 && (ipstack.read(readbuf + len, rem_len, timer.left_ms()) != rem_len))
+        goto exit;
+
+    header.byte = readbuf[0];
+    rc = header.bits.type;
+    if (this->keepAliveInterval > 0)
+        last_received.countdown(this->keepAliveInterval); // record the fact that we have successfully received a packet
+exit:
+
+#if defined(MQTT_DEBUG)
+    if (rc >= 0)
+    {
+        char printbuf[50];
+        DEBUG("Rc %d receiving packet %s\r\n", rc, 
+            MQTTFormat_toClientString(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 MQTT::Client<Network, Timer, a, b>::isTopicMatched(char* topicFilter, MQTTString& 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 MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::deliverMessage(MQTTString& topicName, Message& message)
+{
+    int rc = FAILURE;
+
+    // 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 && (MQTTPacket_equals(&topicName, (char*)messageHandlers[i].topicFilter) ||
+                isTopicMatched((char*)messageHandlers[i].topicFilter, topicName)))
+        {
+            if (messageHandlers[i].fp)  //test to see if it is attached
+            {
+                MessageData md(topicName, message);
+                messageHandlers[i].fp(md);
+                rc = SUCCESS;
+            }
+        }
+    }
+
+    if (rc == FAILURE && defaultMessageHandler )
+    {
+        MessageData md(topicName, message);
+        defaultMessageHandler(md);
+        rc = SUCCESS;
+    }
+
+    return rc;
+}
+
+
+
+template<class Network, class Timer, int a, int b>
+int MQTT::Client<Network, Timer, a, b>::yield(unsigned long timeout_ms)
+{
+    int rc = SUCCESS;
+    Timer timer;
+
+    timer.countdown_ms(timeout_ms);
+    while (!timer.expired())
+    {
+        if (cycle(timer) < 0)
+        {
+            rc = FAILURE;
+            break;
+        }
+    }
+
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::cycle(Timer& timer)
+{
+    // get one piece of work off the wire and one pass through
+    int len = 0,
+        rc = SUCCESS;
+
+    int packet_type = readPacket(timer);    // read the socket, see what work is due
+
+    switch (packet_type)
+    {
+        default:
+            // no more data to read, unrecoverable. Or read packet fails due to unexpected network error
+            rc = packet_type;
+            goto exit;
+        case 0: // timed out reading packet
+            break;
+        case CONNACK:
+        case PUBACK:
+        case SUBACK:
+            break;
+        case PUBLISH:
+        {
+            MQTTString topicName = MQTTString_initializer;
+            Message msg;
+            int intQoS;
+            msg.payloadlen = 0; /* this is a size_t, but deserialize publish sets this as int */
+            if (MQTTDeserialize_publish((unsigned char*)&msg.dup, &intQoS, (unsigned char*)&msg.retained, (unsigned short*)&msg.id, &topicName,
+                                 (unsigned char**)&msg.payload, (int*)&msg.payloadlen, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
+                goto exit;
+            msg.qos = (enum QoS)intQoS;
+#if MQTTCLIENT_QOS2
+            if (msg.qos != QOS2)
+#endif
+                deliverMessage(topicName, msg);
+#if MQTTCLIENT_QOS2
+            else if (isQoS2msgidFree(msg.id))
+            {
+                if (useQoS2msgid(msg.id))
+                    deliverMessage(topicName, msg);
+                else
+                    WARN("Maximum number of incoming QoS2 messages exceeded");
+            }
+#endif
+#if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
+            if (msg.qos != QOS0)
+            {
+                if (msg.qos == QOS1)
+                    len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBACK, 0, msg.id);
+                else if (msg.qos == QOS2)
+                    len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBREC, 0, msg.id);
+                if (len <= 0)
+                    rc = FAILURE;
+                else
+                    rc = sendPacket(len, timer);
+                if (rc == FAILURE)
+                    goto exit; // there was a problem
+            }
+            break;
+#endif
+        }
+#if MQTTCLIENT_QOS2
+        case PUBREC:
+        case PUBREL:
+            unsigned short mypacketid;
+            unsigned char dup, type;
+            if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
+                rc = FAILURE;
+            else if ((len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE,
+                                 (packet_type == PUBREC) ? PUBREL : PUBCOMP, 0, 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
+            if (packet_type == PUBREL)
+                freeQoS2msgid(mypacketid);
+            break;
+
+        case PUBCOMP:
+            break;
+#endif
+        case PINGRESP:
+            ping_outstanding = false;
+            break;
+    }
+
+    if (keepalive() != SUCCESS)
+        //check only keepalive FAILURE status so that previous FAILURE status can be considered as FAULT
+        rc = FAILURE;
+
+exit:
+    if (rc == SUCCESS)
+        rc = packet_type;
+    else if (isconnected)
+        closeSession();
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::keepalive()
+{
+    int rc = SUCCESS;
+    static Timer ping_sent;
+
+    if (keepAliveInterval == 0)
+        goto exit;
+    
+    if (ping_outstanding)
+    {
+        if (ping_sent.expired())
+        {
+            rc = FAILURE; // session failure
+            #if defined(MQTT_DEBUG)
+                DEBUG("PINGRESP not received in keepalive interval\r\n");
+            #endif
+        }
+    }
+    else if (last_sent.expired() || last_received.expired())
+    {
+        Timer timer(1000);
+        int len = MQTTSerialize_pingreq(sendbuf, MAX_MQTT_PACKET_SIZE);
+        if (len > 0 && (rc = sendPacket(len, timer)) == SUCCESS) // send the ping packet
+        {
+            ping_outstanding = true;
+            ping_sent.countdown(this->keepAliveInterval);
+        }
+    }
+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 MQTT::Client<Network, Timer, a, b>::waitfor(int packet_type, Timer& timer)
+{
+    int rc = FAILURE;
+
+    do
+    {
+        if (timer.expired())
+            break; // we timed out
+        rc = cycle(timer);
+    }
+    while (rc != packet_type && rc >= 0);
+
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::connect(MQTTPacket_connectData& options, connackData& data)
+{
+    Timer connect_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->keepAliveInterval = options.keepAliveInterval;
+    this->cleansession = options.cleansession;
+    if ((len = MQTTSerialize_connect(sendbuf, MAX_MQTT_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->keepAliveInterval > 0)
+        last_received.countdown(this->keepAliveInterval);
+    // this will be a blocking call, wait for the connack
+    if (waitfor(CONNACK, connect_timer) == CONNACK)
+    {
+        data.rc = 0;
+        data.sessionPresent = false;
+        if (MQTTDeserialize_connack((unsigned char*)&data.sessionPresent,
+                            (unsigned char*)&data.rc, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
+            rc = data.rc;
+        else
+            rc = FAILURE;
+    }
+    else
+        rc = FAILURE;
+
+#if MQTTCLIENT_QOS2
+    // resend any inflight publish
+    if (inflightMsgid > 0 && inflightQoS == QOS2 && pubrel)
+    {
+        if ((len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBREL, 0, inflightMsgid)) <= 0)
+            rc = FAILURE;
+        else
+            rc = publish(len, connect_timer, inflightQoS);
+    }
+    else
+#endif
+#if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
+    if (inflightMsgid > 0)
+    {
+        memcpy(sendbuf, pubbuf, MAX_MQTT_PACKET_SIZE);
+        rc = publish(inflightLen, connect_timer, inflightQoS);
+    }
+#endif
+
+exit:
+    if (rc == SUCCESS)
+    {
+        isconnected = true;
+        ping_outstanding = false;
+    }
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::connect(MQTTPacket_connectData& options)
+{
+    connackData data;
+    return connect(options, data);
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::connect()
+{
+    MQTTPacket_connectData default_options = MQTTPacket_connectData_initializer;
+    return connect(default_options);
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::setMessageHandler(const char* topicFilter, messageHandler messageHandler)
+{
+    int rc = FAILURE;
+    int i = -1;
+
+    // first check for an existing matching slot
+    for (i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+    {
+        if (messageHandlers[i].topicFilter != 0 && strcmp(messageHandlers[i].topicFilter, topicFilter) == 0)
+        {
+            if (messageHandler == 0) // remove existing
+            {
+                messageHandlers[i].topicFilter = 0;
+                messageHandlers[i].fp.detach();
+            }
+            rc = SUCCESS; // return i when adding new subscription
+            break;
+        }
+    }
+    // if no existing, look for empty slot (unless we are removing)
+    if (messageHandler != 0) {
+        if (rc == FAILURE)
+        {
+            for (i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+            {
+                if (messageHandlers[i].topicFilter == 0)
+                {
+                    rc = SUCCESS;
+                    break;
+                }
+            }
+        }
+        if (i < MAX_MESSAGE_HANDLERS)
+        {
+            messageHandlers[i].topicFilter = topicFilter;
+            messageHandlers[i].fp.attach(messageHandler);
+        }
+    }
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::subscribe(const char* topicFilter,
+     enum QoS qos, messageHandler messageHandler, subackData& data)
+{
+    int rc = FAILURE;
+    Timer timer(command_timeout_ms);
+    int len = 0;
+    MQTTString topic = {(char*)topicFilter, {0, 0}};
+
+    if (!isconnected)
+        goto exit;
+
+    len = MQTTSerialize_subscribe(sendbuf, MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic, (int*)&qos);
+    if (len <= 0)
+        goto exit;
+    if ((rc = sendPacket(len, timer)) != SUCCESS) // send the subscribe packet
+        goto exit;             // there was a problem
+
+    if (waitfor(SUBACK, timer) == SUBACK)      // wait for suback
+    {
+        int count = 0;
+        unsigned short mypacketid;
+        data.grantedQoS = 0;
+        if (MQTTDeserialize_suback(&mypacketid, 1, &count, &data.grantedQoS, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
+        {
+            if (data.grantedQoS != 0x80)
+                rc = setMessageHandler(topicFilter, messageHandler);
+        }
+    }
+    else
+        rc = FAILURE;
+
+exit:
+    if (rc == FAILURE)
+        closeSession();
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::subscribe(const char* topicFilter, enum QoS qos, messageHandler messageHandler)
+{
+    subackData data;
+    return subscribe(topicFilter, qos, messageHandler, data);
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::unsubscribe(const char* topicFilter)
+{
+    int rc = FAILURE;
+    Timer timer(command_timeout_ms);
+    MQTTString topic = {(char*)topicFilter, {0, 0}};
+    int len = 0;
+
+    if (!isconnected)
+        goto exit;
+
+    if ((len = MQTTSerialize_unsubscribe(sendbuf, MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic)) <= 0)
+        goto exit;
+    if ((rc = sendPacket(len, timer)) != SUCCESS) // send the unsubscribe packet
+        goto exit; // there was a problem
+
+    if (waitfor(UNSUBACK, timer) == UNSUBACK)
+    {
+        unsigned short mypacketid;  // should be the same as the packetid above
+        if (MQTTDeserialize_unsuback(&mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
+        {
+            // remove the subscription message handler associated with this topic, if there is one
+            setMessageHandler(topicFilter, 0);
+        }
+    }
+    else
+        rc = FAILURE;
+
+exit:
+    if (rc != SUCCESS)
+        closeSession();
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_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 MQTTCLIENT_QOS1
+    if (qos == QOS1)
+    {
+        if (waitfor(PUBACK, timer) == PUBACK)
+        {
+            unsigned short mypacketid;
+            unsigned char dup, type;
+            if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
+                rc = FAILURE;
+            else if (inflightMsgid == mypacketid)
+                inflightMsgid = 0;
+        }
+        else
+            rc = FAILURE;
+    }
+#endif
+#if MQTTCLIENT_QOS2
+    else if (qos == QOS2)
+    {
+        if (waitfor(PUBCOMP, timer) == PUBCOMP)
+        {
+            unsigned short mypacketid;
+            unsigned char dup, type;
+            if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
+                rc = FAILURE;
+            else if (inflightMsgid == mypacketid)
+                inflightMsgid = 0;
+        }
+        else
+            rc = FAILURE;
+    }
+#endif
+
+exit:
+    if (rc != SUCCESS)
+        closeSession();
+    return rc;
+}
+
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::publish(const char* topicName, void* payload, size_t payloadlen, unsigned short& id, enum QoS qos, bool retained)
+{
+    int rc = FAILURE;
+    Timer timer(command_timeout_ms);
+    MQTTString topicString = MQTTString_initializer;
+    int len = 0;
+
+    if (!isconnected)
+        goto exit;
+
+    topicString.cstring = (char*)topicName;
+
+#if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
+    if (qos == QOS1 || qos == QOS2)
+        id = packetid.getNext();
+#endif
+
+    len = MQTTSerialize_publish(sendbuf, MAX_MQTT_PACKET_SIZE, 0, qos, retained, id,
+              topicString, (unsigned char*)payload, payloadlen);
+    if (len <= 0)
+        goto exit;
+
+#if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
+    if (!cleansession)
+    {
+        memcpy(pubbuf, sendbuf, len);
+        inflightMsgid = id;
+        inflightLen = len;
+        inflightQoS = qos;
+#if MQTTCLIENT_QOS2
+        pubrel = false;
+#endif
+    }
+#endif
+
+    rc = publish(len, timer, qos);
+exit:
+    return rc;
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::publish(const char* 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_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::publish(const char* topicName, Message& message)
+{
+    return publish(topicName, message.payload, message.payloadlen, message.qos, message.retained);
+}
+
+
+template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
+int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::disconnect()
+{
+    int rc = FAILURE;
+    Timer timer(command_timeout_ms);     // we might wait for incomplete incoming publishes to complete
+    int len = MQTTSerialize_disconnect(sendbuf, MAX_MQTT_PACKET_SIZE);
+    if (len > 0)
+        rc = sendPacket(len, timer);            // send the disconnect packet
+    closeSession();
+    return rc;
+}
+
+#endif
diff -r 000000000000 -r 5cd4781e0c88 MQTTLogging.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTLogging.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,39 @@
+#if !defined(MQTT_LOGGING_H)
+#define MQTT_LOGGING_H
+
+#define STREAM      stdout
+#if !defined(DEBUG)
+#define DEBUG(...)    \
+    {\
+    fprintf(STREAM, "DEBUG:   %s L#%d ", __PRETTY_FUNCTION__, __LINE__);  \
+    fprintf(STREAM, ##__VA_ARGS__); \
+    fflush(STREAM); \
+    }
+#endif
+#if !defined(LOG)
+#define LOG(...)    \
+    {\
+    fprintf(STREAM, "LOG:   %s L#%d ", __PRETTY_FUNCTION__, __LINE__);  \
+    fprintf(STREAM, ##__VA_ARGS__); \
+    fflush(STREAM); \
+    }
+#endif
+#if !defined(WARN)
+#define WARN(...)   \
+    { \
+    fprintf(STREAM, "WARN:  %s L#%d ", __PRETTY_FUNCTION__, __LINE__);  \
+    fprintf(STREAM, ##__VA_ARGS__); \
+    fflush(STREAM); \
+    }
+#endif 
+#if !defined(ERROR)
+#define ERROR(...)  \
+    { \
+    fprintf(STREAM, "ERROR: %s L#%d ", __PRETTY_FUNCTION__, __LINE__); \
+    fprintf(STREAM, ##__VA_ARGS__); \
+    fflush(STREAM); \
+    exit(1); \
+    }
+#endif
+
+#endif
\ No newline at end of file
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTConnect.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTConnect.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,149 @@
+/*******************************************************************************
+ * Copyright (c) 2014, 2017 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
+ *    Ian Craggs - add connack return code definitions 
+ *    Xiang Rong - 442039 Add makefile to Embedded C client
+ *    Ian Craggs - fix for issue #64, bit order in connack response
+ *******************************************************************************/
+
+#ifndef MQTTCONNECT_H_
+#define MQTTCONNECT_H_
+
+enum connack_return_codes
+{
+    MQTT_CONNECTION_ACCEPTED = 0,
+    MQTT_UNNACCEPTABLE_PROTOCOL = 1,
+    MQTT_CLIENTID_REJECTED = 2,
+    MQTT_SERVER_UNAVAILABLE = 3,
+    MQTT_BAD_USERNAME_OR_PASSWORD = 4,
+    MQTT_NOT_AUTHORIZED = 5,
+};
+
+#if !defined(DLLImport)
+  #define DLLImport
+#endif
+#if !defined(DLLExport)
+  #define DLLExport
+#endif
+
+
+typedef union
+{
+	unsigned char all;	/**< all connect flags */
+#if defined(REVERSED)
+	struct
+	{
+		unsigned int username : 1;			/**< 3.1 user name */
+		unsigned int password : 1; 			/**< 3.1 password */
+		unsigned int willRetain : 1;		/**< will retain setting */
+		unsigned int willQoS : 2;				/**< will QoS value */
+		unsigned int will : 1;			    /**< will flag */
+		unsigned int cleansession : 1;	  /**< clean session flag */
+		unsigned int : 1;	  	          /**< unused */
+	} bits;
+#else
+	struct
+	{
+		unsigned int : 1;	     					/**< unused */
+		unsigned int cleansession : 1;	  /**< cleansession flag */
+		unsigned int will : 1;			    /**< will flag */
+		unsigned int willQoS : 2;				/**< will QoS value */
+		unsigned int willRetain : 1;		/**< will retain setting */
+		unsigned int password : 1; 			/**< 3.1 password */
+		unsigned int username : 1;			/**< 3.1 user name */
+	} bits;
+#endif
+} MQTTConnectFlags;	/**< connect flags byte */
+
+
+
+/**
+ * Defines the MQTT "Last Will and Testament" (LWT) settings for
+ * the connect packet.
+ */
+typedef struct
+{
+	/** The eyecatcher for this structure.  must be MQTW. */
+	char struct_id[4];
+	/** The version number of this structure.  Must be 0 */
+	int struct_version;
+	/** The LWT topic to which the LWT message will be published. */
+	MQTTString topicName;
+	/** The LWT payload. */
+	MQTTString message;
+	/**
+      * The retained flag for the LWT message (see MQTTAsync_message.retained).
+      */
+	unsigned char retained;
+	/**
+      * The quality of service setting for the LWT message (see
+      * MQTTAsync_message.qos and @ref qos).
+      */
+	char qos;
+} MQTTPacket_willOptions;
+
+
+#define MQTTPacket_willOptions_initializer { {'M', 'Q', 'T', 'W'}, 0, {NULL, {0, NULL}}, {NULL, {0, NULL}}, 0, 0 }
+
+
+typedef struct
+{
+	/** The eyecatcher for this structure.  must be MQTC. */
+	char struct_id[4];
+	/** The version number of this structure.  Must be 0 */
+	int struct_version;
+	/** Version of MQTT to be used.  3 = 3.1 4 = 3.1.1
+	  */
+	unsigned char MQTTVersion;
+	MQTTString clientID;
+	unsigned short keepAliveInterval;
+	unsigned char cleansession;
+	unsigned char willFlag;
+	MQTTPacket_willOptions will;
+	MQTTString username;
+	MQTTString password;
+} MQTTPacket_connectData;
+
+typedef union
+{
+	unsigned char all;	/**< all connack flags */
+#if defined(REVERSED)
+	struct
+	{
+    	unsigned int reserved : 7;	  	    /**< unused */
+		unsigned int sessionpresent : 1;    /**< session present flag */
+	} bits;
+#else
+	struct
+	{
+		unsigned int sessionpresent : 1;    /**< session present flag */
+    	unsigned int reserved: 7;	     	/**< unused */
+	} bits;
+#endif
+} MQTTConnackFlags;	/**< connack flags byte */
+
+#define MQTTPacket_connectData_initializer { {'M', 'Q', 'T', 'C'}, 0, 4, {NULL, {0, NULL}}, 60, 1, 0, \
+		MQTTPacket_willOptions_initializer, {NULL, {0, NULL}}, {NULL, {0, NULL}} }
+
+DLLExport int MQTTSerialize_connect(unsigned char* buf, int buflen, MQTTPacket_connectData* options);
+DLLExport int MQTTDeserialize_connect(MQTTPacket_connectData* data, unsigned char* buf, int len);
+
+DLLExport int MQTTSerialize_connack(unsigned char* buf, int buflen, unsigned char connack_rc, unsigned char sessionPresent);
+DLLExport int MQTTDeserialize_connack(unsigned char* sessionPresent, unsigned char* connack_rc, unsigned char* buf, int buflen);
+
+DLLExport int MQTTSerialize_disconnect(unsigned char* buf, int buflen);
+DLLExport int MQTTSerialize_pingreq(unsigned char* buf, int buflen);
+
+#endif /* MQTTCONNECT_H_ */
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTConnectClient.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTConnectClient.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,215 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+/**
+  * Determines the length of the MQTT connect packet that would be produced using the supplied connect options.
+  * @param options the options to be used to build the connect packet
+  * @return the length of buffer needed to contain the serialized version of the packet
+  */
+int MQTTSerialize_connectLength(MQTTPacket_connectData* options)
+{
+	int len = 0;
+
+	FUNC_ENTRY;
+
+	if (options->MQTTVersion == 3)
+		len = 12; /* variable depending on MQTT or MQIsdp */
+	else if (options->MQTTVersion == 4)
+		len = 10;
+
+	len += MQTTstrlen(options->clientID)+2;
+	if (options->willFlag)
+		len += MQTTstrlen(options->will.topicName)+2 + MQTTstrlen(options->will.message)+2;
+	if (options->username.cstring || options->username.lenstring.data)
+		len += MQTTstrlen(options->username)+2;
+	if (options->password.cstring || options->password.lenstring.data)
+		len += MQTTstrlen(options->password)+2;
+
+	FUNC_EXIT_RC(len);
+	return len;
+}
+
+
+/**
+  * Serializes the connect options into the buffer.
+  * @param buf the buffer into which the packet will be serialized
+  * @param len the length in bytes of the supplied buffer
+  * @param options the options to be used to build the connect packet
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_connect(unsigned char* buf, int buflen, MQTTPacket_connectData* options)
+{
+	unsigned char *ptr = buf;
+	MQTTHeader header = {0};
+	MQTTConnectFlags flags = {0};
+	int len = 0;
+	int rc = -1;
+
+	FUNC_ENTRY;
+	if (MQTTPacket_len(len = MQTTSerialize_connectLength(options)) > buflen)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+
+	header.byte = 0;
+	header.bits.type = CONNECT;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, len); /* write remaining length */
+
+	if (options->MQTTVersion == 4)
+	{
+		writeCString(&ptr, "MQTT");
+		writeChar(&ptr, (char) 4);
+	}
+	else
+	{
+		writeCString(&ptr, "MQIsdp");
+		writeChar(&ptr, (char) 3);
+	}
+
+	flags.all = 0;
+	flags.bits.cleansession = options->cleansession;
+	flags.bits.will = (options->willFlag) ? 1 : 0;
+	if (flags.bits.will)
+	{
+		flags.bits.willQoS = options->will.qos;
+		flags.bits.willRetain = options->will.retained;
+	}
+
+	if (options->username.cstring || options->username.lenstring.data)
+		flags.bits.username = 1;
+	if (options->password.cstring || options->password.lenstring.data)
+		flags.bits.password = 1;
+
+	writeChar(&ptr, flags.all);
+	writeInt(&ptr, options->keepAliveInterval);
+	writeMQTTString(&ptr, options->clientID);
+	if (options->willFlag)
+	{
+		writeMQTTString(&ptr, options->will.topicName);
+		writeMQTTString(&ptr, options->will.message);
+	}
+	if (flags.bits.username)
+		writeMQTTString(&ptr, options->username);
+	if (flags.bits.password)
+		writeMQTTString(&ptr, options->password);
+
+	rc = ptr - buf;
+
+	exit: FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Deserializes the supplied (wire) buffer into connack data - return code
+  * @param sessionPresent the session present flag returned (only for MQTT 3.1.1)
+  * @param connack_rc returned integer value of the connack return code
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param len the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success, 0 is failure
+  */
+int MQTTDeserialize_connack(unsigned char* sessionPresent, unsigned char* connack_rc, unsigned char* buf, int buflen)
+{
+	MQTTHeader header = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = NULL;
+	int rc = 0;
+	int mylen;
+	MQTTConnackFlags flags = {0};
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	if (header.bits.type != CONNACK)
+		goto exit;
+
+	curdata += (rc = MQTTPacket_decodeBuf(curdata, &mylen)); /* read remaining length */
+	enddata = curdata + mylen;
+	if (enddata - curdata < 2)
+		goto exit;
+
+	flags.all = readChar(&curdata);
+	*sessionPresent = flags.bits.sessionpresent;
+	*connack_rc = readChar(&curdata);
+
+	rc = 1;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+
+/**
+  * Serializes a 0-length packet into the supplied buffer, ready for writing to a socket
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer, to avoid overruns
+  * @param packettype the message type
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_zero(unsigned char* buf, int buflen, unsigned char packettype)
+{
+	MQTTHeader header = {0};
+	int rc = -1;
+	unsigned char *ptr = buf;
+
+	FUNC_ENTRY;
+	if (buflen < 2)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+	header.byte = 0;
+	header.bits.type = packettype;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, 0); /* write remaining length */
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Serializes a disconnect packet into the supplied buffer, ready for writing to a socket
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer, to avoid overruns
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_disconnect(unsigned char* buf, int buflen)
+{
+	return MQTTSerialize_zero(buf, buflen, DISCONNECT);
+}
+
+
+/**
+  * Serializes a disconnect packet into the supplied buffer, ready for writing to a socket
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer, to avoid overruns
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_pingreq(unsigned char* buf, int buflen)
+{
+	return MQTTSerialize_zero(buf, buflen, PINGREQ);
+}
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTConnectServer.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTConnectServer.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,148 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "StackTrace.h"
+#include "MQTTPacket.h"
+#include <string.h>
+
+#define min(a, b) ((a < b) ? a : b)
+
+
+/**
+  * Validates MQTT protocol name and version combinations
+  * @param protocol the MQTT protocol name as an MQTTString
+  * @param version the MQTT protocol version number, as in the connect packet
+  * @return correct MQTT combination?  1 is true, 0 is false
+  */
+int MQTTPacket_checkVersion(MQTTString* protocol, int version)
+{
+	int rc = 0;
+
+	if (version == 3 && memcmp(protocol->lenstring.data, "MQIdsp",
+			min(6, protocol->lenstring.len)) == 0)
+		rc = 1;
+	else if (version == 4 && memcmp(protocol->lenstring.data, "MQTT",
+			min(4, protocol->lenstring.len)) == 0)
+		rc = 1;
+	return rc;
+}
+
+
+/**
+  * Deserializes the supplied (wire) buffer into connect data structure
+  * @param data the connect data structure to be filled out
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param len the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success, 0 is failure
+  */
+int MQTTDeserialize_connect(MQTTPacket_connectData* data, unsigned char* buf, int len)
+{
+	MQTTHeader header = {0};
+	MQTTConnectFlags flags = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = &buf[len];
+	int rc = 0;
+	MQTTString Protocol;
+	int version;
+	int mylen = 0;
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	if (header.bits.type != CONNECT)
+		goto exit;
+
+	curdata += MQTTPacket_decodeBuf(curdata, &mylen); /* read remaining length */
+
+	if (!readMQTTLenString(&Protocol, &curdata, enddata) ||
+		enddata - curdata < 0) /* do we have enough data to read the protocol version byte? */
+		goto exit;
+
+	version = (int)readChar(&curdata); /* Protocol version */
+	/* If we don't recognize the protocol version, we don't parse the connect packet on the
+	 * basis that we don't know what the format will be.
+	 */
+	if (MQTTPacket_checkVersion(&Protocol, version))
+	{
+		flags.all = readChar(&curdata);
+		data->cleansession = flags.bits.cleansession;
+		data->keepAliveInterval = readInt(&curdata);
+		if (!readMQTTLenString(&data->clientID, &curdata, enddata))
+			goto exit;
+		if (flags.bits.will)
+		{
+			data->willFlag = 1;
+			data->will.qos = flags.bits.willQoS;
+			data->will.retained = flags.bits.willRetain;
+			if (!readMQTTLenString(&data->will.topicName, &curdata, enddata) ||
+				  !readMQTTLenString(&data->will.message, &curdata, enddata))
+				goto exit;
+		}
+		if (flags.bits.username)
+		{
+			if (enddata - curdata < 3 || !readMQTTLenString(&data->username, &curdata, enddata))
+				goto exit; /* username flag set, but no username supplied - invalid */
+			if (flags.bits.password &&
+				(enddata - curdata < 3 || !readMQTTLenString(&data->password, &curdata, enddata)))
+				goto exit; /* password flag set, but no password supplied - invalid */
+		}
+		else if (flags.bits.password)
+			goto exit; /* password flag set without username - invalid */
+		rc = 1;
+	}
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Serializes the connack packet into the supplied buffer.
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param connack_rc the integer connack return code to be used 
+  * @param sessionPresent the MQTT 3.1.1 sessionPresent flag
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_connack(unsigned char* buf, int buflen, unsigned char connack_rc, unsigned char sessionPresent)
+{
+	MQTTHeader header = {0};
+	int rc = 0;
+	unsigned char *ptr = buf;
+	MQTTConnackFlags flags = {0};
+
+	FUNC_ENTRY;
+	if (buflen < 2)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+	header.byte = 0;
+	header.bits.type = CONNACK;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, 2); /* write remaining length */
+
+	flags.all = 0;
+	flags.bits.sessionpresent = sessionPresent;
+	writeChar(&ptr, flags.all); 
+	writeChar(&ptr, connack_rc);
+
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTDeserializePublish.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTDeserializePublish.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,107 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "StackTrace.h"
+#include "MQTTPacket.h"
+#include <string.h>
+
+#define min(a, b) ((a < b) ? 1 : 0)
+
+/**
+  * Deserializes the supplied (wire) buffer into publish data
+  * @param dup returned integer - the MQTT dup flag
+  * @param qos returned integer - the MQTT QoS value
+  * @param retained returned integer - the MQTT retained flag
+  * @param packetid returned integer - the MQTT packet identifier
+  * @param topicName returned MQTTString - the MQTT topic in the publish
+  * @param payload returned byte buffer - the MQTT publish payload
+  * @param payloadlen returned integer - the length of the MQTT payload
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success
+  */
+int MQTTDeserialize_publish(unsigned char* dup, int* qos, unsigned char* retained, unsigned short* packetid, MQTTString* topicName,
+		unsigned char** payload, int* payloadlen, unsigned char* buf, int buflen)
+{
+	MQTTHeader header = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = NULL;
+	int rc = 0;
+	int mylen = 0;
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	if (header.bits.type != PUBLISH)
+		goto exit;
+	*dup = header.bits.dup;
+	*qos = header.bits.qos;
+	*retained = header.bits.retain;
+
+	curdata += (rc = MQTTPacket_decodeBuf(curdata, &mylen)); /* read remaining length */
+	enddata = curdata + mylen;
+
+	if (!readMQTTLenString(topicName, &curdata, enddata) ||
+		enddata - curdata < 0) /* do we have enough data to read the protocol version byte? */
+		goto exit;
+
+	if (*qos > 0)
+		*packetid = readInt(&curdata);
+
+	*payloadlen = enddata - curdata;
+	*payload = curdata;
+	rc = 1;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+
+/**
+  * Deserializes the supplied (wire) buffer into an ack
+  * @param packettype returned integer - the MQTT packet type
+  * @param dup returned integer - the MQTT dup flag
+  * @param packetid returned integer - the MQTT packet identifier
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success, 0 is failure
+  */
+int MQTTDeserialize_ack(unsigned char* packettype, unsigned char* dup, unsigned short* packetid, unsigned char* buf, int buflen)
+{
+	MQTTHeader header = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = NULL;
+	int rc = 0;
+	int mylen;
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	*dup = header.bits.dup;
+	*packettype = header.bits.type;
+
+	curdata += (rc = MQTTPacket_decodeBuf(curdata, &mylen)); /* read remaining length */
+	enddata = curdata + mylen;
+
+	if (enddata - curdata < 2)
+		goto exit;
+	*packetid = readInt(&curdata);
+
+	rc = 1;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTFormat.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTFormat.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,259 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "StackTrace.h"
+#include "MQTTPacket.h"
+
+#include <string.h>
+
+
+const char* MQTTPacket_names[] =
+{
+    "RESERVED", "CONNECT", "CONNACK", "PUBLISH", "PUBACK", "PUBREC", "PUBREL",
+    "PUBCOMP", "SUBSCRIBE", "SUBACK", "UNSUBSCRIBE", "UNSUBACK",
+    "PINGREQ", "PINGRESP", "DISCONNECT"
+};
+
+
+const char* MQTTPacket_getName(unsigned short packetid)
+{
+    return MQTTPacket_names[packetid];
+}
+
+
+int MQTTStringFormat_connect(char* strbuf, int strbuflen, MQTTPacket_connectData* data)
+{
+    int strindex = 0;
+
+    strindex = snprintf(strbuf, strbuflen,
+            "CONNECT MQTT version %d, client id %.*s, clean session %d, keep alive %d",
+            (int)data->MQTTVersion, data->clientID.lenstring.len, data->clientID.lenstring.data,
+            (int)data->cleansession, data->keepAliveInterval);
+    if (data->willFlag)
+        strindex += snprintf(&strbuf[strindex], strbuflen - strindex,
+                ", will QoS %d, will retain %d, will topic %.*s, will message %.*s",
+                data->will.qos, data->will.retained,
+                data->will.topicName.lenstring.len, data->will.topicName.lenstring.data,
+                data->will.message.lenstring.len, data->will.message.lenstring.data);
+    if (data->username.lenstring.data && data->username.lenstring.len > 0)
+        strindex += snprintf(&strbuf[strindex], strbuflen - strindex,
+                ", user name %.*s", data->username.lenstring.len, data->username.lenstring.data);
+    if (data->password.lenstring.data && data->password.lenstring.len > 0)
+        strindex += snprintf(&strbuf[strindex], strbuflen - strindex,
+                ", password %.*s", data->password.lenstring.len, data->password.lenstring.data);
+    return strindex;
+}
+
+
+int MQTTStringFormat_connack(char* strbuf, int strbuflen, unsigned char connack_rc, unsigned char sessionPresent)
+{
+    int strindex = snprintf(strbuf, strbuflen, "CONNACK session present %d, rc %d", sessionPresent, connack_rc);
+    return strindex;
+}
+
+
+int MQTTStringFormat_publish(char* strbuf, int strbuflen, unsigned char dup, int qos, unsigned char retained,
+        unsigned short packetid, MQTTString topicName, unsigned char* payload, int payloadlen)
+{
+    int strindex = snprintf(strbuf, strbuflen,
+                "PUBLISH dup %d, QoS %d, retained %d, packet id %d, topic %.*s, payload length %d, payload %.*s",
+                dup, qos, retained, packetid,
+                (topicName.lenstring.len < 20) ? topicName.lenstring.len : 20, topicName.lenstring.data,
+                payloadlen, (payloadlen < 20) ? payloadlen : 20, payload);
+    return strindex;
+}
+
+
+int MQTTStringFormat_ack(char* strbuf, int strbuflen, unsigned char packettype, unsigned char dup, unsigned short packetid)
+{
+    int strindex = snprintf(strbuf, strbuflen, "%s, packet id %d", MQTTPacket_names[packettype], packetid);
+    if (dup)
+        strindex += snprintf(strbuf + strindex, strbuflen - strindex, ", dup %d", dup);
+    return strindex;
+}
+
+
+int MQTTStringFormat_subscribe(char* strbuf, int strbuflen, unsigned char dup, unsigned short packetid, int count,
+        MQTTString topicFilters[], int requestedQoSs[])
+{
+    return snprintf(strbuf, strbuflen,
+        "SUBSCRIBE dup %d, packet id %d count %d topic %.*s qos %d",
+        dup, packetid, count,
+        topicFilters[0].lenstring.len, topicFilters[0].lenstring.data,
+        requestedQoSs[0]);
+}
+
+
+int MQTTStringFormat_suback(char* strbuf, int strbuflen, unsigned short packetid, int count, int* grantedQoSs)
+{
+    return snprintf(strbuf, strbuflen,
+        "SUBACK packet id %d count %d granted qos %d", packetid, count, grantedQoSs[0]);
+}
+
+
+int MQTTStringFormat_unsubscribe(char* strbuf, int strbuflen, unsigned char dup, unsigned short packetid,
+        int count, MQTTString topicFilters[])
+{
+    return snprintf(strbuf, strbuflen,
+                    "UNSUBSCRIBE dup %d, packet id %d count %d topic %.*s",
+                    dup, packetid, count,
+                    topicFilters[0].lenstring.len, topicFilters[0].lenstring.data);
+}
+
+
+#if defined(MQTT_CLIENT)
+char* MQTTFormat_toClientString(char* strbuf, int strbuflen, unsigned char* buf, int buflen)
+{
+    int index = 0;
+    int rem_length = 0;
+    MQTTHeader header = {0};
+
+    header.byte = buf[index++];
+    index += MQTTPacket_decodeBuf(&buf[index], &rem_length);
+
+    switch (header.bits.type)
+    {
+
+    case CONNACK:
+    {
+        unsigned char sessionPresent, connack_rc;
+        if (MQTTDeserialize_connack(&sessionPresent, &connack_rc, buf, buflen) == 1)
+            MQTTStringFormat_connack(strbuf, strbuflen, connack_rc, sessionPresent);
+    }
+    break;
+    case PUBLISH:
+    {
+        unsigned char dup, retained, *payload;
+        unsigned short packetid;
+        int qos, payloadlen;
+        MQTTString topicName = MQTTString_initializer;
+        if (MQTTDeserialize_publish(&dup, &qos, &retained, &packetid, &topicName,
+                &payload, &payloadlen, buf, buflen) == 1)
+            MQTTStringFormat_publish(strbuf, strbuflen, dup, qos, retained, packetid,
+                    topicName, payload, payloadlen);
+    }
+    break;
+    case PUBACK:
+    case PUBREC:
+    case PUBREL:
+    case PUBCOMP:
+    {
+        unsigned char packettype, dup;
+        unsigned short packetid;
+        if (MQTTDeserialize_ack(&packettype, &dup, &packetid, buf, buflen) == 1)
+            MQTTStringFormat_ack(strbuf, strbuflen, packettype, dup, packetid);
+    }
+    break;
+    case SUBACK:
+    {
+        unsigned short packetid;
+        int maxcount = 1, count = 0;
+        int grantedQoSs[1];
+        if (MQTTDeserialize_suback(&packetid, maxcount, &count, grantedQoSs, buf, buflen) == 1)
+            MQTTStringFormat_suback(strbuf, strbuflen, packetid, count, grantedQoSs);
+    }
+    break;
+    case UNSUBACK:
+    {
+        unsigned short packetid;
+        if (MQTTDeserialize_unsuback(&packetid, buf, buflen) == 1)
+            MQTTStringFormat_ack(strbuf, strbuflen, UNSUBACK, 0, packetid);
+    }
+    break;
+    case PINGREQ:
+    case PINGRESP:
+    case DISCONNECT:
+        snprintf(strbuf, strbuflen, "%s", MQTTPacket_names[header.bits.type]);
+        break;
+    }
+    return strbuf;
+}
+#endif
+
+#if defined(MQTT_SERVER)
+char* MQTTFormat_toServerString(char* strbuf, int strbuflen, unsigned char* buf, int buflen)
+{
+    int index = 0;
+    int rem_length = 0;
+    MQTTHeader header = {0};
+
+    header.byte = buf[index++];
+    index += MQTTPacket_decodeBuf(&buf[index], &rem_length);
+
+    switch (header.bits.type)
+    {
+    case CONNECT:
+    {
+        MQTTPacket_connectData data;
+        if ((MQTTDeserialize_connect(&data, buf, buflen)) == 1)
+            MQTTStringFormat_connect(strbuf, strbuflen, &data);
+    }
+    break;
+    case PUBLISH:
+    {
+        unsigned char dup, retained, *payload;
+        unsigned short packetid;
+        int qos, payloadlen;
+        MQTTString topicName = MQTTString_initializer;
+        if (MQTTDeserialize_publish(&dup, &qos, &retained, &packetid, &topicName,
+                &payload, &payloadlen, buf, buflen) == 1)
+            MQTTStringFormat_publish(strbuf, strbuflen, dup, qos, retained, packetid,
+                    topicName, payload, payloadlen);
+    }
+    break;
+    case PUBACK:
+    case PUBREC:
+    case PUBREL:
+    case PUBCOMP:
+    {
+        unsigned char packettype, dup;
+        unsigned short packetid;
+        if (MQTTDeserialize_ack(&packettype, &dup, &packetid, buf, buflen) == 1)
+            MQTTStringFormat_ack(strbuf, strbuflen, packettype, dup, packetid);
+    }
+    break;
+    case SUBSCRIBE:
+    {
+        unsigned char dup;
+        unsigned short packetid;
+        int maxcount = 1, count = 0;
+        MQTTString topicFilters[1];
+        int requestedQoSs[1];
+        if (MQTTDeserialize_subscribe(&dup, &packetid, maxcount, &count,
+                topicFilters, requestedQoSs, buf, buflen) == 1)
+            MQTTStringFormat_subscribe(strbuf, strbuflen, dup, packetid, count, topicFilters, requestedQoSs);;
+    }
+    break;
+    case UNSUBSCRIBE:
+    {
+        unsigned char dup;
+        unsigned short packetid;
+        int maxcount = 1, count = 0;
+        MQTTString topicFilters[1];
+        if (MQTTDeserialize_unsubscribe(&dup, &packetid, maxcount, &count, topicFilters, buf, buflen) == 1)
+            MQTTStringFormat_unsubscribe(strbuf, strbuflen, dup, packetid, count, topicFilters);
+    }
+    break;
+    case PINGREQ:
+    case PINGRESP:
+    case DISCONNECT:
+        snprintf(strbuf, strbuflen, "%s", MQTTPacket_names[header.bits.type]);
+        break;
+    }
+    strbuf[strbuflen] = '\0';
+    return strbuf;
+}
+#endif
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTFormat.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTFormat.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,40 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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(MQTTFORMAT_H)
+#define MQTTFORMAT_H
+
+#define MQTT_CLIENT
+#define MQTT_SERVER
+
+#include "StackTrace.h"
+#include "MQTTPacket.h"
+
+const char* MQTTPacket_getName(unsigned short packetid);
+int MQTTStringFormat_connect(char* strbuf, int strbuflen, MQTTPacket_connectData* data);
+int MQTTStringFormat_connack(char* strbuf, int strbuflen, unsigned char connack_rc, unsigned char sessionPresent);
+int MQTTStringFormat_publish(char* strbuf, int strbuflen, unsigned char dup, int qos, unsigned char retained,
+        unsigned short packetid, MQTTString topicName, unsigned char* payload, int payloadlen);
+int MQTTStringFormat_ack(char* strbuf, int strbuflen, unsigned char packettype, unsigned char dup, unsigned short packetid);
+int MQTTStringFormat_subscribe(char* strbuf, int strbuflen, unsigned char dup, unsigned short packetid, int count,
+        MQTTString topicFilters[], int requestedQoSs[]);
+int MQTTStringFormat_suback(char* strbuf, int strbuflen, unsigned short packetid, int count, int* grantedQoSs);
+int MQTTStringFormat_unsubscribe(char* strbuf, int strbuflen, unsigned char dup, unsigned short packetid,
+        int count, MQTTString topicFilters[]);
+char* MQTTFormat_toClientString(char* strbuf, int strbuflen, unsigned char* buf, int buflen);
+char* MQTTFormat_toServerString(char* strbuf, int strbuflen, unsigned char* buf, int buflen);
+
+#endif
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTPacket.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTPacket.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,411 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *    Sergio R. Caprile - non-blocking packet read functions for stream transport
+ *******************************************************************************/
+
+#include "StackTrace.h"
+#include "MQTTPacket.h"
+
+#include <string.h>
+
+/**
+ * Encodes the message length according to the MQTT algorithm
+ * @param buf the buffer into which the encoded data is written
+ * @param length the length to be encoded
+ * @return the number of bytes written to buffer
+ */
+int MQTTPacket_encode(unsigned char* buf, int length)
+{
+	int rc = 0;
+
+	FUNC_ENTRY;
+	do
+	{
+		char d = length % 128;
+		length /= 128;
+		/* if there are more digits to encode, set the top bit of this digit */
+		if (length > 0)
+			d |= 0x80;
+		buf[rc++] = d;
+	} while (length > 0);
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+ * Decodes the message length according to the MQTT algorithm
+ * @param getcharfn pointer to function to read the next character from the data source
+ * @param value the decoded length returned
+ * @return the number of bytes read from the socket
+ */
+int MQTTPacket_decode(int (*getcharfn)(unsigned char*, int), int* value)
+{
+	unsigned char c;
+	int multiplier = 1;
+	int len = 0;
+#define MAX_NO_OF_REMAINING_LENGTH_BYTES 4
+
+	FUNC_ENTRY;
+	*value = 0;
+	do
+	{
+		int rc = MQTTPACKET_READ_ERROR;
+
+		if (++len > MAX_NO_OF_REMAINING_LENGTH_BYTES)
+		{
+			rc = MQTTPACKET_READ_ERROR;	/* bad data */
+			goto exit;
+		}
+		rc = (*getcharfn)(&c, 1);
+		if (rc != 1)
+			goto exit;
+		*value += (c & 127) * multiplier;
+		multiplier *= 128;
+	} while ((c & 128) != 0);
+exit:
+	FUNC_EXIT_RC(len);
+	return len;
+}
+
+
+int MQTTPacket_len(int rem_len)
+{
+	rem_len += 1; /* header byte */
+
+	/* now remaining_length field */
+	if (rem_len < 128)
+		rem_len += 1;
+	else if (rem_len < 16384)
+		rem_len += 2;
+	else if (rem_len < 2097151)
+		rem_len += 3;
+	else
+		rem_len += 4;
+	return rem_len;
+}
+
+
+static unsigned char* bufptr;
+
+int bufchar(unsigned char* c, int count)
+{
+	int i;
+
+	for (i = 0; i < count; ++i)
+		*c = *bufptr++;
+	return count;
+}
+
+
+int MQTTPacket_decodeBuf(unsigned char* buf, int* value)
+{
+	bufptr = buf;
+	return MQTTPacket_decode(bufchar, value);
+}
+
+
+/**
+ * Calculates an integer from two bytes read from the input buffer
+ * @param pptr pointer to the input buffer - incremented by the number of bytes used & returned
+ * @return the integer value calculated
+ */
+int readInt(unsigned char** pptr)
+{
+	unsigned char* ptr = *pptr;
+	int len = 256*(*ptr) + (*(ptr+1));
+	*pptr += 2;
+	return len;
+}
+
+
+/**
+ * Reads one character from the input buffer.
+ * @param pptr pointer to the input buffer - incremented by the number of bytes used & returned
+ * @return the character read
+ */
+char readChar(unsigned char** pptr)
+{
+	char c = **pptr;
+	(*pptr)++;
+	return c;
+}
+
+
+/**
+ * Writes one character to an output buffer.
+ * @param pptr pointer to the output buffer - incremented by the number of bytes used & returned
+ * @param c the character to write
+ */
+void writeChar(unsigned char** pptr, char c)
+{
+	**pptr = c;
+	(*pptr)++;
+}
+
+
+/**
+ * Writes an integer as 2 bytes to an output buffer.
+ * @param pptr pointer to the output buffer - incremented by the number of bytes used & returned
+ * @param anInt the integer to write
+ */
+void writeInt(unsigned char** pptr, int anInt)
+{
+	**pptr = (unsigned char)(anInt / 256);
+	(*pptr)++;
+	**pptr = (unsigned char)(anInt % 256);
+	(*pptr)++;
+}
+
+
+/**
+ * Writes a "UTF" string to an output buffer.  Converts C string to length-delimited.
+ * @param pptr pointer to the output buffer - incremented by the number of bytes used & returned
+ * @param string the C string to write
+ */
+void writeCString(unsigned char** pptr, const char* string)
+{
+	int len = strlen(string);
+	writeInt(pptr, len);
+	memcpy(*pptr, string, len);
+	*pptr += len;
+}
+
+
+int getLenStringLen(char* ptr)
+{
+	int len = 256*((unsigned char)(*ptr)) + (unsigned char)(*(ptr+1));
+	return len;
+}
+
+
+void writeMQTTString(unsigned char** pptr, MQTTString mqttstring)
+{
+	if (mqttstring.lenstring.len > 0)
+	{
+		writeInt(pptr, mqttstring.lenstring.len);
+		memcpy(*pptr, mqttstring.lenstring.data, mqttstring.lenstring.len);
+		*pptr += mqttstring.lenstring.len;
+	}
+	else if (mqttstring.cstring)
+		writeCString(pptr, mqttstring.cstring);
+	else
+		writeInt(pptr, 0);
+}
+
+
+/**
+ * @param mqttstring the MQTTString structure into which the data is to be read
+ * @param pptr pointer to the output buffer - incremented by the number of bytes used & returned
+ * @param enddata pointer to the end of the data: do not read beyond
+ * @return 1 if successful, 0 if not
+ */
+int readMQTTLenString(MQTTString* mqttstring, unsigned char** pptr, unsigned char* enddata)
+{
+	int rc = 0;
+
+	FUNC_ENTRY;
+	/* the first two bytes are the length of the string */
+	if (enddata - (*pptr) > 1) /* enough length to read the integer? */
+	{
+		mqttstring->lenstring.len = readInt(pptr); /* increments pptr to point past length */
+		if (&(*pptr)[mqttstring->lenstring.len] <= enddata)
+		{
+			mqttstring->lenstring.data = (char*)*pptr;
+			*pptr += mqttstring->lenstring.len;
+			rc = 1;
+		}
+	}
+	mqttstring->cstring = NULL;
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+ * Return the length of the MQTTstring - C string if there is one, otherwise the length delimited string
+ * @param mqttstring the string to return the length of
+ * @return the length of the string
+ */
+int MQTTstrlen(MQTTString mqttstring)
+{
+	int rc = 0;
+
+	if (mqttstring.cstring)
+		rc = strlen(mqttstring.cstring);
+	else
+		rc = mqttstring.lenstring.len;
+	return rc;
+}
+
+
+/**
+ * Compares an MQTTString to a C string
+ * @param a the MQTTString to compare
+ * @param bptr the C string to compare
+ * @return boolean - equal or not
+ */
+int MQTTPacket_equals(MQTTString* a, char* bptr)
+{
+	int alen = 0,
+		blen = 0;
+	char *aptr;
+	
+	if (a->cstring)
+	{
+		aptr = a->cstring;
+		alen = strlen(a->cstring);
+	}
+	else
+	{
+		aptr = a->lenstring.data;
+		alen = a->lenstring.len;
+	}
+	blen = strlen(bptr);
+	
+	return (alen == blen) && (strncmp(aptr, bptr, alen) == 0);
+}
+
+
+/**
+ * Helper function to read packet data from some source into a buffer
+ * @param buf the buffer into which the packet will be serialized
+ * @param buflen the length in bytes of the supplied buffer
+ * @param getfn pointer to a function which will read any number of bytes from the needed source
+ * @return integer MQTT packet type, or -1 on error
+ * @note  the whole message must fit into the caller's buffer
+ */
+int MQTTPacket_read(unsigned char* buf, int buflen, int (*getfn)(unsigned char*, int))
+{
+	int rc = -1;
+	MQTTHeader header = {0};
+	int len = 0;
+	int rem_len = 0;
+
+	/* 1. read the header byte.  This has the packet type in it */
+	if ((*getfn)(buf, 1) != 1)
+		goto exit;
+
+	len = 1;
+	/* 2. read the remaining length.  This is variable in itself */
+	MQTTPacket_decode(getfn, &rem_len);
+	len += MQTTPacket_encode(buf + 1, rem_len); /* put the original remaining length back into the buffer */
+
+	/* 3. read the rest of the buffer using a callback to supply the rest of the data */
+	if((rem_len + len) > buflen)
+		goto exit;
+	if (rem_len && ((*getfn)(buf + len, rem_len) != rem_len))
+		goto exit;
+
+	header.byte = buf[0];
+	rc = header.bits.type;
+exit:
+	return rc;
+}
+
+/**
+ * Decodes the message length according to the MQTT algorithm, non-blocking
+ * @param trp pointer to a transport structure holding what is needed to solve getting data from it
+ * @param value the decoded length returned
+ * @return integer the number of bytes read from the socket, 0 for call again, or -1 on error
+ */
+static int MQTTPacket_decodenb(MQTTTransport *trp)
+{
+	unsigned char c;
+	int rc = MQTTPACKET_READ_ERROR;
+
+	FUNC_ENTRY;
+	if(trp->len == 0){		/* initialize on first call */
+		trp->multiplier = 1;
+		trp->rem_len = 0;
+	}
+	do {
+		int frc;
+		if (trp->len >= MAX_NO_OF_REMAINING_LENGTH_BYTES)
+			goto exit;
+		if ((frc=(*trp->getfn)(trp->sck, &c, 1)) == -1)
+			goto exit;
+		if (frc == 0){
+			rc = 0;
+			goto exit;
+		}
+		++(trp->len);
+		trp->rem_len += (c & 127) * trp->multiplier;
+		trp->multiplier *= 128;
+	} while ((c & 128) != 0);
+	rc = trp->len;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+/**
+ * Helper function to read packet data from some source into a buffer, non-blocking
+ * @param buf the buffer into which the packet will be serialized
+ * @param buflen the length in bytes of the supplied buffer
+ * @param trp pointer to a transport structure holding what is needed to solve getting data from it
+ * @return integer MQTT packet type, 0 for call again, or -1 on error
+ * @note  the whole message must fit into the caller's buffer
+ */
+int MQTTPacket_readnb(unsigned char* buf, int buflen, MQTTTransport *trp)
+{
+	int rc = -1, frc;
+	MQTTHeader header = {0};
+
+	switch(trp->state){
+	default:
+		trp->state = 0;
+		/*FALLTHROUGH*/
+	case 0:
+		/* read the header byte.  This has the packet type in it */
+		if ((frc=(*trp->getfn)(trp->sck, buf, 1)) == -1)
+			goto exit;
+		if (frc == 0)
+			return 0;
+		trp->len = 0;
+		++trp->state;
+		/*FALLTHROUGH*/
+		/* read the remaining length.  This is variable in itself */
+	case 1:
+		if((frc=MQTTPacket_decodenb(trp)) == MQTTPACKET_READ_ERROR)
+			goto exit;
+		if(frc == 0)
+			return 0;
+		trp->len = 1 + MQTTPacket_encode(buf + 1, trp->rem_len); /* put the original remaining length back into the buffer */
+		if((trp->rem_len + trp->len) > buflen)
+			goto exit;
+		++trp->state;
+		/*FALLTHROUGH*/
+	case 2:
+		if(trp->rem_len){
+			/* read the rest of the buffer using a callback to supply the rest of the data */
+			if ((frc=(*trp->getfn)(trp->sck, buf + trp->len, trp->rem_len)) == -1)
+				goto exit;
+			if (frc == 0)
+				return 0;
+			trp->rem_len -= frc;
+			trp->len += frc;
+			if(trp->rem_len)
+				return 0;
+		}
+		header.byte = buf[0];
+		rc = header.bits.type;
+		break;
+	}
+
+exit:
+	trp->state = 0;
+	return rc;
+}
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTPacket.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTPacket.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,133 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *    Xiang Rong - 442039 Add makefile to Embedded C client
+ *******************************************************************************/
+
+#ifndef MQTTPACKET_H_
+#define MQTTPACKET_H_
+
+#if defined(__cplusplus) /* If this is a C++ compiler, use C linkage */
+extern "C" {
+#endif
+
+#if defined(WIN32_DLL) || defined(WIN64_DLL)
+  #define DLLImport __declspec(dllimport)
+  #define DLLExport __declspec(dllexport)
+#elif defined(LINUX_SO)
+  #define DLLImport extern
+  #define DLLExport  __attribute__ ((visibility ("default")))
+#else
+  #define DLLImport
+  #define DLLExport  
+#endif
+
+enum errors
+{
+	MQTTPACKET_BUFFER_TOO_SHORT = -2,
+	MQTTPACKET_READ_ERROR = -1,
+	MQTTPACKET_READ_COMPLETE
+};
+
+enum msgTypes
+{
+	CONNECT = 1, CONNACK, PUBLISH, PUBACK, PUBREC, PUBREL,
+	PUBCOMP, SUBSCRIBE, SUBACK, UNSUBSCRIBE, UNSUBACK,
+	PINGREQ, PINGRESP, DISCONNECT
+};
+
+/**
+ * Bitfields for the MQTT header byte.
+ */
+typedef union
+{
+	unsigned char byte;	                /**< the whole byte */
+#if defined(REVERSED)
+	struct
+	{
+		unsigned int type : 4;			/**< message type nibble */
+		unsigned int dup : 1;				/**< DUP flag bit */
+		unsigned int qos : 2;				/**< QoS value, 0, 1 or 2 */
+		unsigned int retain : 1;		/**< retained flag bit */
+	} bits;
+#else
+	struct
+	{
+		unsigned int retain : 1;		/**< retained flag bit */
+		unsigned int qos : 2;				/**< QoS value, 0, 1 or 2 */
+		unsigned int dup : 1;				/**< DUP flag bit */
+		unsigned int type : 4;			/**< message type nibble */
+	} bits;
+#endif
+} MQTTHeader;
+
+typedef struct
+{
+	int len;
+	char* data;
+} MQTTLenString;
+
+typedef struct
+{
+	char* cstring;
+	MQTTLenString lenstring;
+} MQTTString;
+
+#define MQTTString_initializer {NULL, {0, NULL}}
+
+int MQTTstrlen(MQTTString mqttstring);
+
+#include "MQTTConnect.h"
+#include "MQTTPublish.h"
+#include "MQTTSubscribe.h"
+#include "MQTTUnsubscribe.h"
+#include "MQTTFormat.h"
+
+DLLExport int MQTTSerialize_ack(unsigned char* buf, int buflen, unsigned char type, unsigned char dup, unsigned short packetid);
+DLLExport int MQTTDeserialize_ack(unsigned char* packettype, unsigned char* dup, unsigned short* packetid, unsigned char* buf, int buflen);
+
+int MQTTPacket_len(int rem_len);
+DLLExport int MQTTPacket_equals(MQTTString* a, char* b);
+
+DLLExport int MQTTPacket_encode(unsigned char* buf, int length);
+int MQTTPacket_decode(int (*getcharfn)(unsigned char*, int), int* value);
+int MQTTPacket_decodeBuf(unsigned char* buf, int* value);
+
+int readInt(unsigned char** pptr);
+char readChar(unsigned char** pptr);
+void writeChar(unsigned char** pptr, char c);
+void writeInt(unsigned char** pptr, int anInt);
+int readMQTTLenString(MQTTString* mqttstring, unsigned char** pptr, unsigned char* enddata);
+void writeCString(unsigned char** pptr, const char* string);
+void writeMQTTString(unsigned char** pptr, MQTTString mqttstring);
+
+DLLExport int MQTTPacket_read(unsigned char* buf, int buflen, int (*getfn)(unsigned char*, int));
+
+typedef struct {
+	int (*getfn)(void *, unsigned char*, int); /* must return -1 for error, 0 for call again, or the number of bytes read */
+	void *sck;	/* pointer to whatever the system may use to identify the transport */
+	int multiplier;
+	int rem_len;
+	int len;
+	char state;
+}MQTTTransport;
+
+int MQTTPacket_readnb(unsigned char* buf, int buflen, MQTTTransport *trp);
+
+#ifdef __cplusplus /* If this is a C++ compiler, use C linkage */
+}
+#endif
+
+
+#endif /* MQTTPACKET_H_ */
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTPublish.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTPublish.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,30 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#ifndef MQTTPUBLISH_H_
+#define MQTTPUBLISH_H_
+
+int MQTTSerialize_publish(unsigned char* buf, int buflen, unsigned char dup, int qos, unsigned char retained, unsigned short packetid,
+		MQTTString topicName, unsigned char* payload, int payloadlen);
+
+int MQTTDeserialize_publish(unsigned char* dup, int* qos, unsigned char* retained, unsigned short* packetid, MQTTString* topicName,
+		unsigned char** payload, int* payloadlen, unsigned char* buf, int len);
+
+int MQTTSerialize_puback(unsigned char* buf, int buflen, unsigned short packetid);
+int MQTTSerialize_pubrel(unsigned char* buf, int buflen, unsigned char dup, unsigned short packetid);
+int MQTTSerialize_pubcomp(unsigned char* buf, int buflen, unsigned short packetid);
+
+#endif /* MQTTPUBLISH_H_ */
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTSerializePublish.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTSerializePublish.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,168 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *    Ian Craggs - fix for https://bugs.eclipse.org/bugs/show_bug.cgi?id=453144
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+
+/**
+  * Determines the length of the MQTT publish packet that would be produced using the supplied parameters
+  * @param qos the MQTT QoS of the publish (packetid is omitted for QoS 0)
+  * @param topicName the topic name to be used in the publish  
+  * @param payloadlen the length of the payload to be sent
+  * @return the length of buffer needed to contain the serialized version of the packet
+  */
+int MQTTSerialize_publishLength(int qos, MQTTString topicName, int payloadlen)
+{
+	int len = 0;
+
+	len += 2 + MQTTstrlen(topicName) + payloadlen;
+	if (qos > 0)
+		len += 2; /* packetid */
+	return len;
+}
+
+
+/**
+  * Serializes the supplied publish data into the supplied buffer, ready for sending
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param dup integer - the MQTT dup flag
+  * @param qos integer - the MQTT QoS value
+  * @param retained integer - the MQTT retained flag
+  * @param packetid integer - the MQTT packet identifier
+  * @param topicName MQTTString - the MQTT topic in the publish
+  * @param payload byte buffer - the MQTT publish payload
+  * @param payloadlen integer - the length of the MQTT payload
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTSerialize_publish(unsigned char* buf, int buflen, unsigned char dup, int qos, unsigned char retained, unsigned short packetid,
+		MQTTString topicName, unsigned char* payload, int payloadlen)
+{
+	unsigned char *ptr = buf;
+	MQTTHeader header = {0};
+	int rem_len = 0;
+	int rc = 0;
+
+	FUNC_ENTRY;
+	if (MQTTPacket_len(rem_len = MQTTSerialize_publishLength(qos, topicName, payloadlen)) > buflen)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+
+	header.bits.type = PUBLISH;
+	header.bits.dup = dup;
+	header.bits.qos = qos;
+	header.bits.retain = retained;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, rem_len); /* write remaining length */;
+
+	writeMQTTString(&ptr, topicName);
+
+	if (qos > 0)
+		writeInt(&ptr, packetid);
+
+	memcpy(ptr, payload, payloadlen);
+	ptr += payloadlen;
+
+	rc = ptr - buf;
+
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+
+/**
+  * Serializes the ack packet into the supplied buffer.
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param type the MQTT packet type
+  * @param dup the MQTT dup flag
+  * @param packetid the MQTT packet identifier
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_ack(unsigned char* buf, int buflen, unsigned char packettype, unsigned char dup, unsigned short packetid)
+{
+	MQTTHeader header = {0};
+	int rc = 0;
+	unsigned char *ptr = buf;
+
+	FUNC_ENTRY;
+	if (buflen < 4)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+	header.bits.type = packettype;
+	header.bits.dup = dup;
+	header.bits.qos = (packettype == PUBREL) ? 1 : 0;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, 2); /* write remaining length */
+	writeInt(&ptr, packetid);
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Serializes a puback packet into the supplied buffer.
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param packetid integer - the MQTT packet identifier
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_puback(unsigned char* buf, int buflen, unsigned short packetid)
+{
+	return MQTTSerialize_ack(buf, buflen, PUBACK, 0, packetid);
+}
+
+
+/**
+  * Serializes a pubrel packet into the supplied buffer.
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param dup integer - the MQTT dup flag
+  * @param packetid integer - the MQTT packet identifier
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_pubrel(unsigned char* buf, int buflen, unsigned char dup, unsigned short packetid)
+{
+	return MQTTSerialize_ack(buf, buflen, PUBREL, dup, packetid);
+}
+
+
+/**
+  * Serializes a pubrel packet into the supplied buffer.
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param packetid integer - the MQTT packet identifier
+  * @return serialized length, or error if 0
+  */
+int MQTTSerialize_pubcomp(unsigned char* buf, int buflen, unsigned short packetid)
+{
+	return MQTTSerialize_ack(buf, buflen, PUBCOMP, 0, packetid);
+}
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTSubscribe.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTSubscribe.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,31 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#ifndef MQTTSUBSCRIBE_H_
+#define MQTTSUBSCRIBE_H_
+
+int MQTTSerialize_subscribe(unsigned char* buf, int buflen, unsigned char dup, unsigned short packetid,
+		int count, MQTTString topicFilters[], int requestedQoSs[]);
+
+int MQTTDeserialize_subscribe(unsigned char* dup, unsigned short* packetid,
+		int maxcount, int* count, MQTTString topicFilters[], int requestedQoSs[], unsigned char* buf, int len);
+
+int MQTTSerialize_suback(unsigned char* buf, int buflen, unsigned short packetid, int count, int* grantedQoSs);
+
+int MQTTDeserialize_suback(unsigned short* packetid, int maxcount, int* count, int grantedQoSs[], unsigned char* buf, int len);
+
+
+#endif /* MQTTSUBSCRIBE_H_ */
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTSubscribeClient.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTSubscribeClient.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,137 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+/**
+  * Determines the length of the MQTT subscribe packet that would be produced using the supplied parameters
+  * @param count the number of topic filter strings in topicFilters
+  * @param topicFilters the array of topic filter strings to be used in the publish
+  * @return the length of buffer needed to contain the serialized version of the packet
+  */
+int MQTTSerialize_subscribeLength(int count, MQTTString topicFilters[])
+{
+	int i;
+	int len = 2; /* packetid */
+
+	for (i = 0; i < count; ++i)
+		len += 2 + MQTTstrlen(topicFilters[i]) + 1; /* length + topic + req_qos */
+	return len;
+}
+
+
+/**
+  * Serializes the supplied subscribe data into the supplied buffer, ready for sending
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied bufferr
+  * @param dup integer - the MQTT dup flag
+  * @param packetid integer - the MQTT packet identifier
+  * @param count - number of members in the topicFilters and reqQos arrays
+  * @param topicFilters - array of topic filter names
+  * @param requestedQoSs - array of requested QoS
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTSerialize_subscribe(unsigned char* buf, int buflen, unsigned char dup, unsigned short packetid, int count,
+		MQTTString topicFilters[], int requestedQoSs[])
+{
+	unsigned char *ptr = buf;
+	MQTTHeader header = {0};
+	int rem_len = 0;
+	int rc = 0;
+	int i = 0;
+
+	FUNC_ENTRY;
+	if (MQTTPacket_len(rem_len = MQTTSerialize_subscribeLength(count, topicFilters)) > buflen)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+
+	header.byte = 0;
+	header.bits.type = SUBSCRIBE;
+	header.bits.dup = dup;
+	header.bits.qos = 1;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, rem_len); /* write remaining length */;
+
+	writeInt(&ptr, packetid);
+
+	for (i = 0; i < count; ++i)
+	{
+		writeMQTTString(&ptr, topicFilters[i]);
+		writeChar(&ptr, requestedQoSs[i]);
+	}
+
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+
+/**
+  * Deserializes the supplied (wire) buffer into suback data
+  * @param packetid returned integer - the MQTT packet identifier
+  * @param maxcount - the maximum number of members allowed in the grantedQoSs array
+  * @param count returned integer - number of members in the grantedQoSs array
+  * @param grantedQoSs returned array of integers - the granted qualities of service
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success, 0 is failure
+  */
+int MQTTDeserialize_suback(unsigned short* packetid, int maxcount, int* count, int grantedQoSs[], unsigned char* buf, int buflen)
+{
+	MQTTHeader header = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = NULL;
+	int rc = 0;
+	int mylen;
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	if (header.bits.type != SUBACK)
+		goto exit;
+
+	curdata += (rc = MQTTPacket_decodeBuf(curdata, &mylen)); /* read remaining length */
+	enddata = curdata + mylen;
+	if (enddata - curdata < 2)
+		goto exit;
+
+	*packetid = readInt(&curdata);
+
+	*count = 0;
+	while (curdata < enddata)
+	{
+		if (*count > maxcount)
+		{
+			rc = -1;
+			goto exit;
+		}
+		grantedQoSs[(*count)++] = readChar(&curdata);
+	}
+
+	rc = 1;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTSubscribeServer.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTSubscribeServer.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,112 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+
+/**
+  * Deserializes the supplied (wire) buffer into subscribe data
+  * @param dup integer returned - the MQTT dup flag
+  * @param packetid integer returned - the MQTT packet identifier
+  * @param maxcount - the maximum number of members allowed in the topicFilters and requestedQoSs arrays
+  * @param count - number of members in the topicFilters and requestedQoSs arrays
+  * @param topicFilters - array of topic filter names
+  * @param requestedQoSs - array of requested QoS
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTDeserialize_subscribe(unsigned char* dup, unsigned short* packetid, int maxcount, int* count, MQTTString topicFilters[],
+	int requestedQoSs[], unsigned char* buf, int buflen)
+{
+	MQTTHeader header = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = NULL;
+	int rc = -1;
+	int mylen = 0;
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	if (header.bits.type != SUBSCRIBE)
+		goto exit;
+	*dup = header.bits.dup;
+
+	curdata += (rc = MQTTPacket_decodeBuf(curdata, &mylen)); /* read remaining length */
+	enddata = curdata + mylen;
+
+	*packetid = readInt(&curdata);
+
+	*count = 0;
+	while (curdata < enddata)
+	{
+		if (!readMQTTLenString(&topicFilters[*count], &curdata, enddata))
+			goto exit;
+		if (curdata >= enddata) /* do we have enough data to read the req_qos version byte? */
+			goto exit;
+		requestedQoSs[*count] = readChar(&curdata);
+		(*count)++;
+	}
+
+	rc = 1;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Serializes the supplied suback data into the supplied buffer, ready for sending
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param packetid integer - the MQTT packet identifier
+  * @param count - number of members in the grantedQoSs array
+  * @param grantedQoSs - array of granted QoS
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTSerialize_suback(unsigned char* buf, int buflen, unsigned short packetid, int count, int* grantedQoSs)
+{
+	MQTTHeader header = {0};
+	int rc = -1;
+	unsigned char *ptr = buf;
+	int i;
+
+	FUNC_ENTRY;
+	if (buflen < 2 + count)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+	header.byte = 0;
+	header.bits.type = SUBACK;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, 2 + count); /* write remaining length */
+
+	writeInt(&ptr, packetid);
+
+	for (i = 0; i < count; ++i)
+		writeChar(&ptr, grantedQoSs[i]);
+
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTUnsubscribe.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTUnsubscribe.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,30 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#ifndef MQTTUNSUBSCRIBE_H_
+#define MQTTUNSUBSCRIBE_H_
+
+int MQTTSerialize_unsubscribe(unsigned char* buf, int buflen, unsigned char dup, unsigned short packetid,
+		int count, MQTTString topicFilters[]);
+
+int MQTTDeserialize_unsubscribe(unsigned char* dup, unsigned short* packetid, int max_count, int* count, MQTTString topicFilters[],
+		unsigned char* buf, int len);
+
+int MQTTSerialize_unsuback(unsigned char* buf, int buflen, unsigned short packetid);
+
+int MQTTDeserialize_unsuback(unsigned short* packetid, unsigned char* buf, int len);
+
+#endif /* MQTTUNSUBSCRIBE_H_ */
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTUnsubscribeClient.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTUnsubscribeClient.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,106 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+/**
+  * Determines the length of the MQTT unsubscribe packet that would be produced using the supplied parameters
+  * @param count the number of topic filter strings in topicFilters
+  * @param topicFilters the array of topic filter strings to be used in the publish
+  * @return the length of buffer needed to contain the serialized version of the packet
+  */
+int MQTTSerialize_unsubscribeLength(int count, MQTTString topicFilters[])
+{
+	int i;
+	int len = 2; /* packetid */
+
+	for (i = 0; i < count; ++i)
+		len += 2 + MQTTstrlen(topicFilters[i]); /* length + topic*/
+	return len;
+}
+
+
+/**
+  * Serializes the supplied unsubscribe data into the supplied buffer, ready for sending
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @param dup integer - the MQTT dup flag
+  * @param packetid integer - the MQTT packet identifier
+  * @param count - number of members in the topicFilters array
+  * @param topicFilters - array of topic filter names
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTSerialize_unsubscribe(unsigned char* buf, int buflen, unsigned char dup, unsigned short packetid,
+		int count, MQTTString topicFilters[])
+{
+	unsigned char *ptr = buf;
+	MQTTHeader header = {0};
+	int rem_len = 0;
+	int rc = -1;
+	int i = 0;
+
+	FUNC_ENTRY;
+	if (MQTTPacket_len(rem_len = MQTTSerialize_unsubscribeLength(count, topicFilters)) > buflen)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+
+	header.byte = 0;
+	header.bits.type = UNSUBSCRIBE;
+	header.bits.dup = dup;
+	header.bits.qos = 1;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, rem_len); /* write remaining length */;
+
+	writeInt(&ptr, packetid);
+
+	for (i = 0; i < count; ++i)
+		writeMQTTString(&ptr, topicFilters[i]);
+
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Deserializes the supplied (wire) buffer into unsuback data
+  * @param packetid returned integer - the MQTT packet identifier
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success, 0 is failure
+  */
+int MQTTDeserialize_unsuback(unsigned short* packetid, unsigned char* buf, int buflen)
+{
+	unsigned char type = 0;
+	unsigned char dup = 0;
+	int rc = 0;
+
+	FUNC_ENTRY;
+	rc = MQTTDeserialize_ack(&type, &dup, packetid, buf, buflen);
+	if (type == UNSUBACK)
+		rc = 1;
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/MQTTUnsubscribeServer.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/MQTTUnsubscribeServer.c	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,102 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+
+/**
+  * Deserializes the supplied (wire) buffer into unsubscribe data
+  * @param dup integer returned - the MQTT dup flag
+  * @param packetid integer returned - the MQTT packet identifier
+  * @param maxcount - the maximum number of members allowed in the topicFilters and requestedQoSs arrays
+  * @param count - number of members in the topicFilters and requestedQoSs arrays
+  * @param topicFilters - array of topic filter names
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTDeserialize_unsubscribe(unsigned char* dup, unsigned short* packetid, int maxcount, int* count, MQTTString topicFilters[],
+		unsigned char* buf, int len)
+{
+	MQTTHeader header = {0};
+	unsigned char* curdata = buf;
+	unsigned char* enddata = NULL;
+	int rc = 0;
+	int mylen = 0;
+
+	FUNC_ENTRY;
+	header.byte = readChar(&curdata);
+	if (header.bits.type != UNSUBSCRIBE)
+		goto exit;
+	*dup = header.bits.dup;
+
+	curdata += (rc = MQTTPacket_decodeBuf(curdata, &mylen)); /* read remaining length */
+	enddata = curdata + mylen;
+
+	*packetid = readInt(&curdata);
+
+	*count = 0;
+	while (curdata < enddata)
+	{
+		if (!readMQTTLenString(&topicFilters[*count], &curdata, enddata))
+			goto exit;
+		(*count)++;
+	}
+
+	rc = 1;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Serializes the supplied unsuback data into the supplied buffer, ready for sending
+  * @param buf the buffer into which the packet will be serialized
+  * @param buflen the length in bytes of the supplied buffer
+  * @param packetid integer - the MQTT packet identifier
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTSerialize_unsuback(unsigned char* buf, int buflen, unsigned short packetid)
+{
+	MQTTHeader header = {0};
+	int rc = 0;
+	unsigned char *ptr = buf;
+
+	FUNC_ENTRY;
+	if (buflen < 2)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+	header.byte = 0;
+	header.bits.type = UNSUBACK;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, 2); /* write remaining length */
+
+	writeInt(&ptr, packetid);
+
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/StackTrace.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/StackTrace.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,78 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *    Ian Craggs - fix for bug #434081
+ *******************************************************************************/
+
+#ifndef STACKTRACE_H_
+#define STACKTRACE_H_
+
+#include <stdio.h>
+#define NOSTACKTRACE 1
+
+#if defined(NOSTACKTRACE)
+#define FUNC_ENTRY
+#define FUNC_ENTRY_NOLOG
+#define FUNC_ENTRY_MED
+#define FUNC_ENTRY_MAX
+#define FUNC_EXIT
+#define FUNC_EXIT_NOLOG
+#define FUNC_EXIT_MED
+#define FUNC_EXIT_MAX
+#define FUNC_EXIT_RC(x)
+#define FUNC_EXIT_MED_RC(x)
+#define FUNC_EXIT_MAX_RC(x)
+
+#else
+
+#if defined(WIN32)
+#define inline __inline
+#define FUNC_ENTRY StackTrace_entry(__FUNCTION__, __LINE__, TRACE_MINIMUM)
+#define FUNC_ENTRY_NOLOG StackTrace_entry(__FUNCTION__, __LINE__, -1)
+#define FUNC_ENTRY_MED StackTrace_entry(__FUNCTION__, __LINE__, TRACE_MEDIUM)
+#define FUNC_ENTRY_MAX StackTrace_entry(__FUNCTION__, __LINE__, TRACE_MAXIMUM)
+#define FUNC_EXIT StackTrace_exit(__FUNCTION__, __LINE__, NULL, TRACE_MINIMUM)
+#define FUNC_EXIT_NOLOG StackTrace_exit(__FUNCTION__, __LINE__, -1)
+#define FUNC_EXIT_MED StackTrace_exit(__FUNCTION__, __LINE__, NULL, TRACE_MEDIUM)
+#define FUNC_EXIT_MAX StackTrace_exit(__FUNCTION__, __LINE__, NULL, TRACE_MAXIMUM)
+#define FUNC_EXIT_RC(x) StackTrace_exit(__FUNCTION__, __LINE__, &x, TRACE_MINIMUM)
+#define FUNC_EXIT_MED_RC(x) StackTrace_exit(__FUNCTION__, __LINE__, &x, TRACE_MEDIUM)
+#define FUNC_EXIT_MAX_RC(x) StackTrace_exit(__FUNCTION__, __LINE__, &x, TRACE_MAXIMUM)
+#else
+#define FUNC_ENTRY StackTrace_entry(__func__, __LINE__, TRACE_MINIMUM)
+#define FUNC_ENTRY_NOLOG StackTrace_entry(__func__, __LINE__, -1)
+#define FUNC_ENTRY_MED StackTrace_entry(__func__, __LINE__, TRACE_MEDIUM)
+#define FUNC_ENTRY_MAX StackTrace_entry(__func__, __LINE__, TRACE_MAXIMUM)
+#define FUNC_EXIT StackTrace_exit(__func__, __LINE__, NULL, TRACE_MINIMUM)
+#define FUNC_EXIT_NOLOG StackTrace_exit(__func__, __LINE__, NULL, -1)
+#define FUNC_EXIT_MED StackTrace_exit(__func__, __LINE__, NULL, TRACE_MEDIUM)
+#define FUNC_EXIT_MAX StackTrace_exit(__func__, __LINE__, NULL, TRACE_MAXIMUM)
+#define FUNC_EXIT_RC(x) StackTrace_exit(__func__, __LINE__, &x, TRACE_MINIMUM)
+#define FUNC_EXIT_MED_RC(x) StackTrace_exit(__func__, __LINE__, &x, TRACE_MEDIUM)
+#define FUNC_EXIT_MAX_RC(x) StackTrace_exit(__func__, __LINE__, &x, TRACE_MAXIMUM)
+
+void StackTrace_entry(const char* name, int line, int trace);
+void StackTrace_exit(const char* name, int line, void* return_value, int trace);
+
+void StackTrace_printStack(FILE* dest);
+char* StackTrace_get(unsigned long);
+
+#endif
+
+#endif
+
+
+
+
+#endif /* STACKTRACE_H_ */
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/samples/publish-subscribe.txt
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/samples/publish-subscribe.txt	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,115 @@
+#include "MQTTPacket.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "EthernetInterface.h"
+
+
+TCPSocketConnection mysock; 
+
+int getdata(char* buf, int count)
+{
+    return mysock.receive(buf, (size_t)count);
+}
+
+int toStop = 0;
+
+
+int main()
+{
+    MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
+    int rc = 0;
+    char buf[200];
+    int buflen = sizeof(buf);
+    int msgid = 1;
+    MQTTString topicString = MQTTString_initializer;
+    int req_qos = 0;
+    char* payload = "mypayload";
+    int payloadlen = strlen(payload);
+    int len = 0;
+    EthernetInterface eth;
+    
+    eth.init(); //Use DHCP
+    eth.connect();
+
+    rc = mysock.connect("m2m.eclipse.org", 1883);
+
+    data.clientID.cstring = "SendReceive mbed MQTT ";
+    data.keepAliveInterval = 20;
+    data.cleansession = 1;
+
+    mysock.set_blocking(true, 1000);  /* 1 second Timeout */
+
+    len = MQTTSerialize_connect(buf, buflen, &data);
+    rc = mysock.send(buf, len);
+
+    /* wait for connack */
+    if (MQTTPacket_read(buf, buflen, getdata) == CONNACK)
+    {
+        int connack_rc;
+
+        if (MQTTDeserialize_connack(&connack_rc, buf, buflen) != 1 || connack_rc != 0)
+        {
+            printf("Unable to connect, return code %d\n", connack_rc);
+            goto exit;
+        }
+    }
+    else
+        goto exit;
+
+    /* subscribe */
+    topicString.cstring = "substopic";
+    len = MQTTSerialize_subscribe(buf, buflen, 0, msgid, 1, &topicString, &req_qos);
+
+    rc = mysock.send(buf, len);
+    if (MQTTPacket_read(buf, buflen, getdata) == SUBACK)    /* wait for suback */
+    {
+        int submsgid;
+        int subcount;
+        int granted_qos;
+
+        rc = MQTTDeserialize_suback(&submsgid, 1, &subcount, &granted_qos, buf, buflen);
+        if (granted_qos != 0)
+        {
+            printf("granted qos != 0, %d\n", granted_qos);
+            goto exit;
+        }
+    }
+    else
+        goto exit;
+
+    topicString.cstring = "pubtopic";
+    while (!toStop)
+    {
+        if (MQTTPacket_read(buf, buflen, getdata) == PUBLISH)
+        {
+            int dup;
+            int qos;
+            int retained;
+            int msgid;
+            int payloadlen_in;
+            char* payload_in;
+            int rc;
+            MQTTString receivedTopic;
+
+            rc = MQTTDeserialize_publish(&dup, &qos, &retained, &msgid, &receivedTopic,
+                    &payload_in, &payloadlen_in, buf, buflen);
+            printf("message arrived %.*s\n", payloadlen_in, payload_in);
+        }
+
+        printf("publishing reading\n");
+        len = MQTTSerialize_publish(buf, buflen, 0, 0, 0, 0, topicString, payload, payloadlen);
+        rc = mysock.send(buf, len);
+    }
+
+    printf("disconnecting\n");
+    len = MQTTSerialize_disconnect(buf, buflen);
+    rc = mysock.send(buf, len);
+
+exit:    
+    eth.disconnect();
+
+    return 0;
+}
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/samples/simple-publish.txt
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/samples/simple-publish.txt	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,89 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+#include "mbed.h"
+#include "EthernetInterface.h"
+#include "C12832_lcd.h"
+
+#include "MQTTPacket.h"
+
+DigitalOut myled(LED2);
+C12832_LCD lcd;
+
+int publish()
+{
+    MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
+    int rc = 0;
+    char buf[200];
+    int buflen = sizeof(buf);
+    TCPSocketConnection mysock; 
+    MQTTString topicString = MQTTString_initializer;
+    char* payload = "I'm alive!";
+    int payloadlen = strlen(payload);
+    int len = 0;
+    
+    mysock.connect("m2m.eclipse.org", 1883);
+          
+    data.clientID.cstring = "mbed test client - Ian Craggs";
+    data.keepAliveInterval = 20;
+    data.cleansession = 1;
+    data.MQTTVersion = 3;
+
+    len = MQTTSerialize_connect(buf, buflen, &data);
+
+    topicString.cstring = "mbed NXP LPC1768";
+    len += MQTTSerialize_publish(buf + len, buflen - len, 0, 0, 0, 0, topicString, payload, payloadlen);
+
+    len += MQTTSerialize_disconnect(buf + len, buflen - len);
+
+    rc = 0;
+    while (rc < len)
+    {
+        int rc1 = mysock.send(buf, len);
+        if (rc1 == -1)
+        {
+            lcd.printf("Send failed\n");
+            break;
+        }
+        else
+            rc += rc1;
+    }
+    if (rc == len)
+        lcd.printf("Send succeeded\n");
+    wait(0.2);
+
+    return 0;
+}
+
+int main()
+{
+    EthernetInterface eth;
+    eth.init(); //Use DHCP
+    eth.connect();
+    lcd.printf("IP Address is %s\n", eth.getIPAddress());
+    
+    while(1) 
+    {
+        myled = 1;
+        publish();
+        wait(0.2);
+        myled = 0;
+        publish();
+        wait(0.2);
+    }
+    
+    eth.disconnect();
+}
\ No newline at end of file
diff -r 000000000000 -r 5cd4781e0c88 MQTTPacket/test/test1.txt
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTPacket/test/test1.txt	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,631 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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
+ *******************************************************************************/
+
+
+#include "MQTTPacket.h"
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#if !defined(_WINDOWS)
+	#include <sys/time.h>
+  	#include <sys/socket.h>
+	#include <unistd.h>
+  	#include <errno.h>
+#else
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#define MAXHOSTNAMELEN 256
+#define EAGAIN WSAEWOULDBLOCK
+#define EINTR WSAEINTR
+#define EINPROGRESS WSAEINPROGRESS
+#define EWOULDBLOCK WSAEWOULDBLOCK
+#define ENOTCONN WSAENOTCONN
+#define ECONNRESET WSAECONNRESET
+#endif
+
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
+
+struct Options
+{
+	char* connection;         /**< connection to system under test. */
+	char** haconnections;
+	int hacount;
+	int verbose;
+	int test_no;
+} options =
+{
+	"tcp://m2m.eclipse.org:1883",
+	NULL,
+	0,
+	0,
+	0,
+};
+
+void usage()
+{
+
+}
+
+void getopts(int argc, char** argv)
+{
+	int count = 1;
+
+	while (count < argc)
+	{
+		if (strcmp(argv[count], "--test_no") == 0)
+		{
+			if (++count < argc)
+				options.test_no = atoi(argv[count]);
+			else
+				usage();
+		}
+		else if (strcmp(argv[count], "--connection") == 0)
+		{
+			if (++count < argc)
+			{
+				options.connection = argv[count];
+				printf("\nSetting connection to %s\n", options.connection);
+			}
+			else
+				usage();
+		}
+		else if (strcmp(argv[count], "--haconnections") == 0)
+		{
+			if (++count < argc)
+			{
+				char* tok = strtok(argv[count], " ");
+				options.hacount = 0;
+				options.haconnections = malloc(sizeof(char*) * 5);
+				while (tok)
+				{
+					options.haconnections[options.hacount] = malloc(strlen(tok) + 1);
+					strcpy(options.haconnections[options.hacount], tok);
+					options.hacount++;
+					tok = strtok(NULL, " ");
+				}
+			}
+			else
+				usage();
+		}
+		else if (strcmp(argv[count], "--verbose") == 0)
+		{
+			options.verbose = 1;
+			printf("\nSetting verbose on\n");
+		}
+		count++;
+	}
+}
+
+
+#define LOGA_DEBUG 0
+#define LOGA_INFO 1
+#include <stdarg.h>
+#include <time.h>
+#include <sys/timeb.h>
+void MyLog(int LOGA_level, char* format, ...)
+{
+	static char msg_buf[256];
+	va_list args;
+	struct timeb ts;
+
+	struct tm *timeinfo;
+
+	if (LOGA_level == LOGA_DEBUG && options.verbose == 0)
+	  return;
+
+	ftime(&ts);
+	timeinfo = localtime(&ts.time);
+	strftime(msg_buf, 80, "%Y%m%d %H%M%S", timeinfo);
+
+	sprintf(&msg_buf[strlen(msg_buf)], ".%.3hu ", ts.millitm);
+
+	va_start(args, format);
+	vsnprintf(&msg_buf[strlen(msg_buf)], sizeof(msg_buf) - strlen(msg_buf), format, args);
+	va_end(args);
+
+	printf("%s\n", msg_buf);
+	fflush(stdout);
+}
+
+
+#if defined(WIN32) || defined(_WINDOWS)
+#define mqsleep(A) Sleep(1000*A)
+#define START_TIME_TYPE DWORD
+static DWORD start_time = 0;
+START_TIME_TYPE start_clock(void)
+{
+	return GetTickCount();
+}
+#elif defined(AIX)
+#define mqsleep sleep
+#define START_TIME_TYPE struct timespec
+START_TIME_TYPE start_clock(void)
+{
+	static struct timespec start;
+	clock_gettime(CLOCK_REALTIME, &start);
+	return start;
+}
+#else
+#define mqsleep sleep
+#define START_TIME_TYPE struct timeval
+/* TODO - unused - remove? static struct timeval start_time; */
+START_TIME_TYPE start_clock(void)
+{
+	struct timeval start_time;
+	gettimeofday(&start_time, NULL);
+	return start_time;
+}
+#endif
+
+
+#if defined(WIN32)
+long elapsed(START_TIME_TYPE start_time)
+{
+	return GetTickCount() - start_time;
+}
+#elif defined(AIX)
+#define assert(a)
+long elapsed(struct timespec start)
+{
+	struct timespec now, res;
+
+	clock_gettime(CLOCK_REALTIME, &now);
+	ntimersub(now, start, res);
+	return (res.tv_sec)*1000L + (res.tv_nsec)/1000000L;
+}
+#else
+long elapsed(START_TIME_TYPE start_time)
+{
+	struct timeval now, res;
+
+	gettimeofday(&now, NULL);
+	timersub(&now, &start_time, &res);
+	return (res.tv_sec)*1000 + (res.tv_usec)/1000;
+}
+#endif
+
+
+#define assert(a, b, c, d) myassert(__FILE__, __LINE__, a, b, c, d)
+#define assert1(a, b, c, d, e) myassert(__FILE__, __LINE__, a, b, c, d, e)
+
+int tests = 0;
+int failures = 0;
+FILE* xml;
+START_TIME_TYPE global_start_time;
+char output[3000];
+char* cur_output = output;
+
+
+void write_test_result()
+{
+	long duration = elapsed(global_start_time);
+
+	fprintf(xml, " time=\"%ld.%.3ld\" >\n", duration / 1000, duration % 1000);
+	if (cur_output != output)
+	{
+		fprintf(xml, "%s", output);
+		cur_output = output;
+	}
+	fprintf(xml, "</testcase>\n");
+}
+
+
+void myassert(char* filename, int lineno, char* description, int value, char* format, ...)
+{
+	++tests;
+	if (!value)
+	{
+		va_list args;
+
+		++failures;
+		printf("Assertion failed, file %s, line %d, description: %s\n", filename, lineno, description);
+
+		va_start(args, format);
+		vprintf(format, args);
+		va_end(args);
+
+		cur_output += sprintf(cur_output, "<failure type=\"%s\">file %s, line %d </failure>\n",
+                        description, filename, lineno);
+	}
+    else
+    	MyLog(LOGA_DEBUG, "Assertion succeeded, file %s, line %d, description: %s", filename, lineno, description);
+}
+
+#define min(a, b) ((a < b) ? a : b)
+
+int checkMQTTStrings(MQTTString a, MQTTString b)
+{
+	if (!a.lenstring.data)
+	{
+		a.lenstring.data = a.cstring;
+		if (a.cstring)
+			a.lenstring.len = strlen(a.cstring);
+	}
+	if (!b.lenstring.data)
+	{
+		b.lenstring.data = b.cstring;
+		if (b.cstring)
+			b.lenstring.len = strlen(b.cstring);
+	}
+	return memcmp(a.lenstring.data, b.lenstring.data, min(a.lenstring.len, b.lenstring.len)) == 0;
+}
+
+
+int checkConnectPackets(MQTTPacket_connectData* before, MQTTPacket_connectData* after)
+{
+	int rc = 0;
+	int start_failures = failures;
+
+	assert("struct_ids should be the same",
+			memcmp(before->struct_id, after->struct_id, 4) == 0, "struct_ids were different %.4s\n", after->struct_id);
+
+	assert("struct_versions should be the same",
+			before->struct_version == after->struct_version, "struct_versions were different\n", rc);
+
+	assert("MQTT versions should be the same",
+			before->MQTTVersion == after->MQTTVersion, "MQTT versions were different\n", rc);
+
+	assert("ClientIDs should be the same",
+			checkMQTTStrings(before->clientID, after->clientID), "ClientIDs were different\n", rc);
+
+	assert("keepAliveIntervals should be the same",
+			before->keepAliveInterval == after->keepAliveInterval, "keepAliveIntervals were different %d\n", after->keepAliveInterval);
+
+	assert("cleansessions should be the same",
+			before->cleansession == after->cleansession, "cleansessions were different\n", rc);
+
+	assert("willFlags should be the same",
+				before->willFlag == after->willFlag, "willFlags were different\n", rc);
+
+	if (before->willFlag)
+	{
+		assert("will struct_ids should be the same",
+				memcmp(before->will.struct_id, after->will.struct_id, 4) == 0, "will struct_ids were different %.4s\n", after->struct_id);
+
+		assert("will struct_versions should be the same",
+				before->will.struct_version == after->will.struct_version, "will struct_versions were different\n", rc);
+
+		assert("topic names should be the same",
+				checkMQTTStrings(before->will.topicName, after->will.topicName), "topic names were different\n", rc);
+
+		assert("messages should be the same",
+				checkMQTTStrings(before->will.message, after->will.message), "messages were different\n", rc);
+
+		assert("retained flags should be the same",
+					before->will.retained == after->will.retained, "retained flags were different\n", rc);
+
+		assert("will qos should be the same",
+					before->will.qos == after->will.qos, "will qos were different\n", rc);
+	}
+
+	assert("usernames should be the same",
+			checkMQTTStrings(before->clientID, after->clientID), "usernames were different\n", rc);
+	assert("passwords should be the same",
+			checkMQTTStrings(before->password, after->password), "passwords were different\n", rc);
+	return failures == start_failures;
+}
+
+int test1(struct Options options)
+{
+	MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
+	MQTTPacket_connectData data_after = MQTTPacket_connectData_initializer;
+	int rc = 0;
+	char buf[100];
+	int buflen = sizeof(buf);
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"de/serialization\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 1 - serialization of connect and back");
+
+	data.clientID.cstring = "me";
+
+	data.keepAliveInterval = 20;
+	data.cleansession = 1;
+	data.username.cstring = "testuser";
+	data.password.cstring = "testpassword";
+
+	data.willFlag = 1;
+	data.will.message.cstring = "will message";
+	data.will.qos = 1;
+	data.will.retained = 0;
+	data.will.topicName.cstring = "will topic";
+
+	rc = MQTTSerialize_connect(buf, buflen, &data);
+	assert("good rc from serialize connect", rc > 0, "rc was %d\n", rc);
+
+	rc = MQTTDeserialize_connect(&data_after, buf, buflen);
+	assert("good rc from deserialize connect", rc == 1, "rc was %d\n", rc);
+
+	/* data after should be the same as data before */
+	rc = checkConnectPackets(&data, &data_after);
+	assert("packets should be the same",  rc == 1, "packets were different\n", rc);
+
+/* exit: */
+	MyLog(LOGA_INFO, "TEST1: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
+int test2(struct Options options)
+{
+	int rc = 0;
+	char buf[100];
+	int buflen = sizeof(buf);
+
+	unsigned char dup = 0;
+	int qos = 2;
+	unsigned char retained = 0;
+	int msgid = 23;
+	MQTTString topicString = MQTTString_initializer;
+	char *payload = "kkhkhkjkj jkjjk jk jk ";
+	int payloadlen = strlen(payload);
+
+	unsigned char dup2 = 1;
+	int qos2 = 1;
+	unsigned char retained2 = 1;
+	int msgid2 = 3243;
+	MQTTString topicString2 = MQTTString_initializer;
+	char *payload2 = NULL;
+	int payloadlen2 = 0;
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"de/serialization\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 2 - serialization of publish and back");
+
+	topicString.cstring = "mytopic";
+	rc = MQTTSerialize_publish(buf, buflen, dup, qos, retained, msgid, topicString,
+			payload, payloadlen);
+	assert("good rc from serialize publish", rc > 0, "rc was %d\n", rc);
+
+	rc = MQTTDeserialize_publish(&dup2, &qos2, &retained2, &msgid2, &topicString2,
+			&payload2, &payloadlen2, buf, buflen);
+	assert("good rc from deserialize publish", rc == 1, "rc was %d\n", rc);
+
+	/* data after should be the same as data before */
+	assert("dups should be the same", dup == dup2, "dups were different %d\n", dup2);
+	assert("qoss should be the same", qos == qos2, "qoss were different %d\n", qos2);
+	assert("retaineds should be the same", retained == retained2, "retaineds were different %d\n", retained2);
+	assert("msgids should be the same", msgid == msgid2, "msgids were different %d\n", msgid2);
+
+	assert("topics should be the same",
+					checkMQTTStrings(topicString, topicString2), "topics were different %s\n", ""); //topicString2);
+
+	assert("payload lengths should be the same",
+				payloadlen == payloadlen2, "payload lengths were different %d\n", payloadlen2);
+
+	assert("payloads should be the same",
+						memcmp(payload, payload2, payloadlen) == 0, "payloads were different %s\n", "");
+
+/*exit:*/
+	MyLog(LOGA_INFO, "TEST2: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
+
+int test3(struct Options options)
+{
+	int i = 0;
+	int rc = 0;
+	char buf[100];
+	int buflen = sizeof(buf);
+#define TOPIC_COUNT 2
+
+	int dup = 0;
+	int msgid = 23;
+	int count = TOPIC_COUNT;
+	MQTTString topicStrings[TOPIC_COUNT] = { MQTTString_initializer, MQTTString_initializer };
+	int req_qoss[TOPIC_COUNT] = {2, 1};
+
+	int dup2 = 1;
+	int msgid2 = 2223;
+	int count2 = 0;
+	MQTTString topicStrings2[TOPIC_COUNT] = { MQTTString_initializer, MQTTString_initializer };
+	int req_qoss2[TOPIC_COUNT] = {0, 0};
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"de/serialization\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 2 - serialization of subscribe and back");
+
+	topicStrings[0].cstring = "mytopic";
+	topicStrings[1].cstring = "mytopic2";
+	rc = MQTTSerialize_subscribe(buf, buflen, dup, msgid, count, topicStrings, req_qoss);
+	assert("good rc from serialize subscribe", rc > 0, "rc was %d\n", rc);
+
+	rc = MQTTDeserialize_subscribe(&dup2, &msgid2, 2, &count2, topicStrings2, req_qoss2, buf, buflen);
+	assert("good rc from deserialize subscribe", rc == 1, "rc was %d\n", rc);
+
+	/* data after should be the same as data before */
+	assert("dups should be the same", dup == dup2, "dups were different %d\n", dup2);
+	assert("msgids should be the same", msgid == msgid2, "msgids were different %d\n", msgid2);
+
+	assert("count should be the same", count == count2, "counts were different %d\n", count2);
+
+	for (i = 0; i < count2; ++i)
+	{
+		assert("topics should be the same",
+					checkMQTTStrings(topicStrings[i], topicStrings2[i]), "topics were different %s\n", "");
+
+		assert("qoss should be the same", req_qoss[i] == req_qoss2[i], "qoss were different %d\n", req_qoss2[i]);
+	}
+
+/*exit:*/
+	MyLog(LOGA_INFO, "TEST3: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
+int test4(struct Options options)
+{
+	int i = 0;
+	int rc = 0;
+	char buf[100];
+	int buflen = sizeof(buf);
+#define TOPIC_COUNT 2
+
+	int msgid = 23;
+	int count = TOPIC_COUNT;
+	int granted_qoss[TOPIC_COUNT] = {2, 1};
+;
+	int msgid2 = 2223;
+	int count2 = 0;
+	int granted_qoss2[TOPIC_COUNT] = {0, 0};
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"de/serialization\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 4 - serialization of suback and back");
+
+	rc = MQTTSerialize_suback(buf, buflen, msgid, count, granted_qoss);
+	assert("good rc from serialize suback", rc > 0, "rc was %d\n", rc);
+
+	rc = MQTTDeserialize_suback(&msgid2, 2, &count2, granted_qoss2, buf, buflen);
+	assert("good rc from deserialize suback", rc == 1, "rc was %d\n", rc);
+
+	/* data after should be the same as data before */
+	assert("msgids should be the same", msgid == msgid2, "msgids were different %d\n", msgid2);
+
+	assert("count should be the same", count == count2, "counts were different %d\n", count2);
+
+	for (i = 0; i < count2; ++i)
+		assert("qoss should be the same", granted_qoss[i] == granted_qoss2[i], "qoss were different %d\n", granted_qoss2[i]);
+
+/* exit: */
+	MyLog(LOGA_INFO, "TEST4: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
+int test5(struct Options options)
+{
+	int i = 0;
+	int rc = 0;
+	char buf[100];
+	int buflen = sizeof(buf);
+#define TOPIC_COUNT 2
+
+	int dup = 0;
+	int msgid = 23;
+	int count = TOPIC_COUNT;
+	MQTTString topicStrings[TOPIC_COUNT] = { MQTTString_initializer, MQTTString_initializer };
+
+	int dup2 = 1;
+	int msgid2 = 2223;
+	int count2 = 0;
+	MQTTString topicStrings2[TOPIC_COUNT] = { MQTTString_initializer, MQTTString_initializer };
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"de/serialization\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 2 - serialization of unsubscribe and back");
+
+	topicStrings[0].cstring = "mytopic";
+	topicStrings[1].cstring = "mytopic2";
+	rc = MQTTSerialize_unsubscribe(buf, buflen, dup, msgid, count, topicStrings);
+	assert("good rc from serialize unsubscribe", rc > 0, "rc was %d\n", rc);
+
+	rc = MQTTDeserialize_unsubscribe(&dup2, &msgid2, 2, &count2, topicStrings2, buf, buflen);
+	assert("good rc from deserialize unsubscribe", rc == 1, "rc was %d\n", rc);
+
+	/* data after should be the same as data before */
+	assert("dups should be the same", dup == dup2, "dups were different %d\n", dup2);
+	assert("msgids should be the same", msgid == msgid2, "msgids were different %d\n", msgid2);
+
+	assert("count should be the same", count == count2, "counts were different %d\n", count2);
+
+	for (i = 0; i < count2; ++i)
+		assert("topics should be the same",
+					checkMQTTStrings(topicStrings[i], topicStrings2[i]), "topics were different %s\n", "");
+
+/* exit: */
+	MyLog(LOGA_INFO, "TEST5: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
+int test6(struct Options options)
+{
+	int rc = 0;
+	char buf[100];
+	int buflen = sizeof(buf);
+
+	int connack_rc = 77;
+
+	int connack_rc2 = 0;
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"de/serialization\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 2 - serialization of connack and back");
+
+	rc = MQTTSerialize_connack(buf, buflen, connack_rc);
+	assert("good rc from serialize connack", rc > 0, "rc was %d\n", rc);
+
+	rc = MQTTDeserialize_connack(&connack_rc2, buf, buflen);
+	assert("good rc from deserialize connack", rc == 1, "rc was %d\n", rc);
+
+	/* data after should be the same as data before */
+	assert("dups should be the same", connack_rc == connack_rc2, "dups were different %d\n", connack_rc2);
+
+/* exit: */
+	MyLog(LOGA_INFO, "TEST6: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
+int main(int argc, char** argv)
+{
+	int rc = 0;
+ 	int (*tests[])() = {NULL, test1, test2, test3, test4, test5, test6};
+
+	xml = fopen("TEST-test1.xml", "w");
+	fprintf(xml, "<testsuite name=\"test1\" tests=\"%d\">\n", (int)(ARRAY_SIZE(tests) - 1));
+
+	getopts(argc, argv);
+
+ 	if (options.test_no == 0)
+	{ /* run all the tests */
+ 	   	for (options.test_no = 1; options.test_no < ARRAY_SIZE(tests); ++options.test_no)
+			rc += tests[options.test_no](options); /* return number of failures.  0 = test succeeded */
+	}
+	else
+ 	   	rc = tests[options.test_no](options); /* run just the selected test */
+
+ 	if (rc == 0)
+		MyLog(LOGA_INFO, "verdict pass");
+	else
+		MyLog(LOGA_INFO, "verdict fail");
+
+	fprintf(xml, "</testsuite>\n");
+	fclose(xml);
+	return rc;
+}
diff -r 000000000000 -r 5cd4781e0c88 MQTTSocket.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTSocket.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,95 @@
+#if !defined(MQTTSOCKET_H)
+#define MQTTSOCKET_H
+
+#include "MQTTmbed.h"
+#include <Timer.h>
+
+class MQTTSocket
+{
+public:
+    MQTTSocket(NetworkInterface *anet) : net(anet)
+    {
+        open = false;
+    }
+    
+    int connect(char* hostname, int port, int timeout=1000)
+    {
+        if (open)
+            disconnect();
+        nsapi_error_t rc = mysock.open(net);
+        open = true;
+        mysock.set_blocking(true);
+        mysock.set_timeout((unsigned int)timeout);  
+        rc = mysock.connect(hostname, port);
+        mysock.set_blocking(false);  // blocking timeouts seem not to work
+        return rc;
+    }
+
+    // common read/write routine, avoiding blocking timeouts
+    int common(unsigned char* buffer, int len, int timeout, bool read)
+    {
+        timer.start();
+        mysock.set_blocking(false); // blocking timeouts seem not to work
+        int bytes = 0;
+        bool first = true;
+        do 
+        {
+            if (first)
+                first = false;
+            else
+                wait_ms(timeout < 100 ? timeout : 100);
+            int rc;
+            if (read)
+                rc = mysock.recv((char*)buffer, len);
+            else
+                rc = mysock.send((char*)buffer, len);
+            if (rc < 0)
+            {
+                if (rc != NSAPI_ERROR_WOULD_BLOCK)
+                {
+                    bytes = -1;
+                    break;
+                }
+            } 
+            else
+                bytes += rc;
+        }
+        while (bytes < len && timer.read_ms() < timeout);
+        timer.stop();
+        return bytes;
+    }
+
+    /* returns the number of bytes read, which could be 0.
+       -1 if there was an error on the socket
+    */
+    int read(unsigned char* buffer, int len, int timeout)
+    {
+        return common(buffer, len, timeout, true);
+    }
+
+    int write(unsigned char* buffer, int len, int timeout)
+    {
+        return common(buffer, len, timeout, false);
+    }
+
+    int disconnect()
+    {
+        open = false;
+        return mysock.close();
+    }
+
+    /*bool is_connected()
+    {
+        return mysock.is_connected();
+    }*/
+
+private:
+
+    bool open;
+    TCPSocket mysock;
+    NetworkInterface *net;
+    Timer timer;
+
+};
+
+#endif
diff -r 000000000000 -r 5cd4781e0c88 MQTTmbed.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTmbed.h	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,48 @@
+#if !defined(MQTT_MBED_H)
+#define MQTT_MBED_H
+
+#include "mbed.h"
+
+class Countdown
+{
+public:
+    Countdown() : t()
+    {
+  
+    }
+    
+    Countdown(int ms) : t()
+    {
+        countdown_ms(ms);   
+    }
+    
+    
+    bool expired()
+    {
+        return t.read_ms() >= interval_end_ms;
+    }
+    
+    void countdown_ms(unsigned long ms)  
+    {
+        t.stop();
+        interval_end_ms = ms;
+        t.reset();
+        t.start();
+    }
+    
+    void countdown(int seconds)
+    {
+        countdown_ms((unsigned long)seconds * 1000L);
+    }
+    
+    int left_ms()
+    {
+        return interval_end_ms - t.read_ms();
+    }
+    
+private:
+    Timer t;
+    long interval_end_ms; 
+};
+
+#endif
diff -r 000000000000 -r 5cd4781e0c88 README.md
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/README.md	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,20 @@
+# MQTT -- An API for using MQTT over multiple transports
+
+This library originated from https://os.mbed.com/teams/mqtt/code/MQTT/ but has been modified to allow you to select different transports by
+modifing the mbed_app.json file. 
+
+## Specifying the connectivity method
+
+Add the following to your `mbed_app.json` file:
+
+```json
+{
+    "config": {
+        "mqtt-interface":{
+            "help": "options are MQTT_ETHERNET, MQTT_WNC14A2A, MQTT_BG96"
+            "value": "MQTT_ETHERNET"
+        }
+    }
+}
+```
+
diff -r 000000000000 -r 5cd4781e0c88 mbed_lib.json
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed_lib.json	Tue Mar 27 17:26:35 2018 +0000
@@ -0,0 +1,10 @@
+{
+    "name": "MQTT",
+    "config": {
+        "mqtt-interface":{
+            "help": "Options are MQTT_ETHERNET, MQTT_WNC14A2A, MQTT_BG96",
+            "value": "MQTT_ETHERNET"
+       }
+    }
+}
+