MQTTClient.h

00001 /*******************************************************************************
00002  * Copyright (c) 2014 IBM Corp.
00003  *
00004  * All rights reserved. This program and the accompanying materials
00005  * are made available under the terms of the Eclipse Public License v1.0
00006  * and Eclipse Distribution License v1.0 which accompany this distribution.
00007  *
00008  * The Eclipse Public License is available at
00009  *    http://www.eclipse.org/legal/epl-v10.html
00010  * and the Eclipse Distribution License is available at
00011  *   http://www.eclipse.org/org/documents/edl-v10.php.
00012  *
00013  * Contributors:
00014  *    Ian Craggs - initial API and implementation and/or initial documentation
00015  *******************************************************************************/
00016 
00017 #if !defined(MQTTCLIENT_H)
00018 #define MQTTCLIENT_H
00019 
00020 #include "FP.h"
00021 #include "MQTTPacket.h"
00022 #include "stdio.h"
00023 #include "MQTTLogging.h"
00024 
00025 #if !defined(MQTTCLIENT_QOS1)
00026     #define MQTTCLIENT_QOS1 1
00027 #endif
00028 #if !defined(MQTTCLIENT_QOS2)
00029     #define MQTTCLIENT_QOS2 0
00030 #endif
00031 
00032 namespace MQTT
00033 {
00034 
00035 
00036 enum QoS { QOS0, QOS1, QOS2 };
00037 
00038 // all failure return codes must be negative
00039 enum returnCode { BUFFER_OVERFLOW = -2, FAILURE = -1, SUCCESS = 0 };
00040 
00041 
00042 struct Message
00043 {
00044     enum QoS qos;
00045     bool retained;
00046     bool dup;
00047     unsigned short id;
00048     void *payload;
00049     size_t payloadlen;
00050 };
00051 
00052 
00053 struct MessageData
00054 {
00055     MessageData(MQTTString &aTopicName, struct Message &aMessage)  : message(aMessage), topicName(aTopicName)
00056     { }
00057 
00058     struct Message &message;
00059     MQTTString &topicName;
00060 };
00061 
00062 
00063 class PacketId
00064 {
00065 public:
00066     PacketId()
00067     {
00068         next = 0;
00069     }
00070 
00071     int getNext()
00072     {
00073         return next = (next == MAX_PACKET_ID) ? 1 : ++next;
00074     }
00075 
00076 private:
00077     static const int MAX_PACKET_ID = 65535;
00078     int next;
00079 };
00080 
00081 
00082 /**
00083  * @class Client
00084  * @brief blocking, non-threaded MQTT client API
00085  *
00086  * This version of the API blocks on all method calls, until they are complete.  This means that only one
00087  * MQTT request can be in process at any one time.
00088  * @param Network a network class which supports send, receive
00089  * @param Timer a timer class with the methods:
00090  */
00091 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE = 500, int MAX_MESSAGE_HANDLERS = 5>
00092 class Client
00093 {
00094 
00095 public:
00096 
00097     typedef void (*messageHandler)(MessageData&);
00098 
00099     /** Construct the client
00100      *  @param network - pointer to an instance of the Network class - must be connected to the endpoint
00101      *      before calling MQTT connect
00102      *  @param limits an instance of the Limit class - to alter limits as required
00103      */
00104     Client(Network& network, unsigned int command_timeout_ms = 30000);
00105 
00106     /** Set the default message handling callback - used for any message which does not match a subscription message handler
00107      *  @param mh - pointer to the callback function
00108      */
00109     void setDefaultMessageHandler(messageHandler mh)
00110     {
00111         defaultMessageHandler.attach(mh);
00112     }
00113 
00114     /** MQTT Connect - send an MQTT connect packet down the network and wait for a Connack
00115      *  The nework object must be connected to the network endpoint before calling this
00116      *  Default connect options are used
00117      *  @return success code -
00118      */
00119     int connect();
00120     
00121     /** MQTT Connect - send an MQTT connect packet down the network and wait for a Connack
00122      *  The nework object must be connected to the network endpoint before calling this
00123      *  @param options - connect options
00124      *  @return success code -
00125      */
00126     int connect(MQTTPacket_connectData& options);
00127 
00128     /** MQTT Publish - send an MQTT publish packet and wait for all acks to complete for all QoSs
00129      *  @param topic - the topic to publish to
00130      *  @param message - the message to send
00131      *  @return success code -
00132      */
00133     int publish(const char* topicName, Message& message);
00134     
00135     /** MQTT Publish - send an MQTT publish packet and wait for all acks to complete for all QoSs
00136      *  @param topic - the topic to publish to
00137      *  @param payload - the data to send
00138      *  @param payloadlen - the length of the data
00139      *  @param qos - the QoS to send the publish at
00140      *  @param retained - whether the message should be retained
00141      *  @return success code -
00142      */
00143     int publish(const char* topicName, void* payload, size_t payloadlen, enum QoS qos = QOS0, bool retained = false);
00144     
00145     /** MQTT Publish - send an MQTT publish packet and wait for all acks to complete for all QoSs
00146      *  @param topic - the topic to publish to
00147      *  @param payload - the data to send
00148      *  @param payloadlen - the length of the data
00149      *  @param id - the packet id used - returned 
00150      *  @param qos - the QoS to send the publish at
00151      *  @param retained - whether the message should be retained
00152      *  @return success code -
00153      */
00154     int publish(const char* topicName, void* payload, size_t payloadlen, unsigned short& id, enum QoS qos = QOS1, bool retained = false);
00155 
00156     /** MQTT Subscribe - send an MQTT subscribe packet and wait for the suback
00157      *  @param topicFilter - a topic pattern which can include wildcards
00158      *  @param qos - the MQTT QoS to subscribe at
00159      *  @param mh - the callback function to be invoked when a message is received for this subscription
00160      *  @return success code -
00161      */
00162     int subscribe(const char* topicFilter, enum QoS qos, messageHandler mh);
00163 
00164     /** MQTT Unsubscribe - send an MQTT unsubscribe packet and wait for the unsuback
00165      *  @param topicFilter - a topic pattern which can include wildcards
00166      *  @return success code -
00167      */
00168     int unsubscribe(const char* topicFilter);
00169 
00170     /** MQTT Disconnect - send an MQTT disconnect packet, and clean up any state
00171      *  @return success code -
00172      */
00173     int disconnect();
00174 
00175     /** A call to this API must be made within the keepAlive interval to keep the MQTT connection alive
00176      *  yield can be called if no other MQTT operation is needed.  This will also allow messages to be
00177      *  received.
00178      *  @param timeout_ms the time to wait, in milliseconds
00179      *  @return success code - on failure, this means the client has disconnected
00180      */
00181     int yield(unsigned long timeout_ms = 1000L);
00182 
00183     /** Is the client connected?
00184      *  @return flag - is the client connected or not?
00185      */
00186     bool isConnected()
00187     {
00188         return isconnected;
00189     }
00190 
00191 private:
00192 
00193     int cycle(Timer& timer);
00194     int waitfor(int packet_type, Timer& timer);
00195     int keepalive();
00196     int publish(int len, Timer& timer, enum QoS qos);
00197 
00198     int decodePacket(int* value, int timeout);
00199     int readPacket(Timer& timer);
00200     int sendPacket(int length, Timer& timer);
00201     int deliverMessage(MQTTString& topicName, Message& message);
00202     bool isTopicMatched(char* topicFilter, MQTTString& topicName);
00203 
00204     Network& ipstack;
00205     unsigned long command_timeout_ms;
00206 
00207     unsigned char sendbuf[MAX_MQTT_PACKET_SIZE];
00208     unsigned char readbuf[MAX_MQTT_PACKET_SIZE];
00209 
00210     Timer last_sent, last_received;
00211     unsigned int keepAliveInterval;
00212     bool ping_outstanding;
00213     bool cleansession;
00214 
00215     PacketId packetid;
00216 
00217     struct MessageHandlers
00218     {
00219         const char* topicFilter;
00220         FP<void, MessageData&> fp;
00221     } messageHandlers[MAX_MESSAGE_HANDLERS];      // Message handlers are indexed by subscription topic
00222 
00223     FP<void, MessageData&> defaultMessageHandler;
00224 
00225     bool isconnected;
00226 
00227 #if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
00228     unsigned char pubbuf[MAX_MQTT_PACKET_SIZE];  // store the last publish for sending on reconnect
00229     int inflightLen;
00230     unsigned short inflightMsgid;
00231     enum QoS inflightQoS;
00232 #endif
00233 
00234 #if MQTTCLIENT_QOS2
00235     bool pubrel;
00236     #if !defined(MAX_INCOMING_QOS2_MESSAGES)
00237         #define MAX_INCOMING_QOS2_MESSAGES 10
00238     #endif
00239     unsigned short incomingQoS2messages[MAX_INCOMING_QOS2_MESSAGES];
00240     bool isQoS2msgidFree(unsigned short id);
00241     bool useQoS2msgid(unsigned short id);
00242 #endif
00243 
00244 };
00245 
00246 }
00247 
00248 
00249 template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
00250 MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::Client(Network& network, unsigned int command_timeout_ms)  : ipstack(network), packetid()
00251 {
00252     last_sent = Timer();
00253     last_received = Timer();
00254     ping_outstanding = false;
00255     for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
00256         messageHandlers[i].topicFilter = 0;
00257     this->command_timeout_ms = command_timeout_ms;
00258     isconnected = false;
00259     
00260 #if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
00261     inflightMsgid = 0;
00262     inflightQoS = QOS0;
00263 #endif
00264 
00265     
00266 #if MQTTCLIENT_QOS2
00267     pubrel = false;
00268     for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
00269         incomingQoS2messages[i] = 0;
00270 #endif
00271 }
00272 
00273 #if MQTTCLIENT_QOS2
00274 template<class Network, class Timer, int a, int b>
00275 bool MQTT::Client<Network, Timer, a, b>::isQoS2msgidFree(unsigned short id)
00276 {
00277     for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
00278     {
00279         if (incomingQoS2messages[i] == id)
00280             return false;
00281     }
00282     return true;
00283 }
00284 
00285 
00286 template<class Network, class Timer, int a, int b>
00287 bool MQTT::Client<Network, Timer, a, b>::useQoS2msgid(unsigned short id)
00288 {
00289     for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
00290     {
00291         if (incomingQoS2messages[i] == 0)
00292         {
00293             incomingQoS2messages[i] = id;
00294             return true;
00295         }
00296     }
00297     return false;
00298 }
00299 #endif
00300 
00301 
00302 template<class Network, class Timer, int a, int b>
00303 int MQTT::Client<Network, Timer, a, b>::sendPacket(int length, Timer& timer)
00304 {
00305     int rc = FAILURE,
00306         sent = 0;
00307 
00308     while (sent < length && !timer.expired())
00309     {
00310         rc = ipstack.write(&sendbuf[sent], length, timer.left_ms());
00311         if (rc < 0)  // there was an error writing the data
00312             break;
00313         sent += rc;
00314     }
00315     if (sent == length)
00316     {
00317         if (this->keepAliveInterval > 0)
00318             last_sent.countdown(this->keepAliveInterval); // record the fact that we have successfully sent the packet
00319         rc = SUCCESS;
00320     }
00321     else
00322         rc = FAILURE;
00323         
00324 #if defined(MQTT_DEBUG)
00325     char printbuf[50];
00326     DEBUG("Rc %d from sending packet %s\n", rc, MQTTPacket_toString(printbuf, sizeof(printbuf), sendbuf, length));
00327 #endif
00328     return rc;
00329 }
00330 
00331 
00332 template<class Network, class Timer, int a, int b>
00333 int MQTT::Client<Network, Timer, a, b>::decodePacket(int* value, int timeout)
00334 {
00335     unsigned char c;
00336     int multiplier = 1;
00337     int len = 0;
00338     const int MAX_NO_OF_REMAINING_LENGTH_BYTES = 4;
00339 
00340     *value = 0;
00341     do
00342     {
00343         int rc = MQTTPACKET_READ_ERROR;
00344 
00345         if (++len > MAX_NO_OF_REMAINING_LENGTH_BYTES)
00346         {
00347             rc = MQTTPACKET_READ_ERROR; /* bad data */
00348             goto exit;
00349         }
00350         rc = ipstack.read(&c, 1, timeout);
00351         if (rc != 1)
00352             goto exit;
00353         *value += (c & 127) * multiplier;
00354         multiplier *= 128;
00355     } while ((c & 128) != 0);
00356 exit:
00357     return len;
00358 }
00359 
00360 
00361 /**
00362  * If any read fails in this method, then we should disconnect from the network, as on reconnect
00363  * the packets can be retried.
00364  * @param timeout the max time to wait for the packet read to complete, in milliseconds
00365  * @return the MQTT packet type, or -1 if none
00366  */
00367 template<class Network, class Timer, int a, int b>
00368 int MQTT::Client<Network, Timer, a, b>::readPacket(Timer& timer)
00369 {
00370     int rc = FAILURE;
00371     MQTTHeader header = {0};
00372     int len = 0;
00373     int rem_len = 0;
00374 
00375     /* 1. read the header byte.  This has the packet type in it */
00376     if (ipstack.read(readbuf, 1, timer.left_ms()) != 1)
00377         goto exit;
00378 
00379     len = 1;
00380     /* 2. read the remaining length.  This is variable in itself */
00381     decodePacket(&rem_len, timer.left_ms());
00382     len += MQTTPacket_encode(readbuf + 1, rem_len); /* put the original remaining length into the buffer */
00383 
00384     /* 3. read the rest of the buffer using a callback to supply the rest of the data */
00385     if (rem_len > 0 && (ipstack.read(readbuf + len, rem_len, timer.left_ms()) != rem_len))
00386         goto exit;
00387 
00388     header.byte = readbuf[0];
00389     rc = header.bits.type;
00390     if (this->keepAliveInterval > 0)
00391         last_received.countdown(this->keepAliveInterval); // record the fact that we have successfully received a packet
00392 exit:
00393         
00394 #if defined(MQTT_DEBUG)
00395     char printbuf[50];
00396     DEBUG("Rc %d from receiving packet %s\n", rc, MQTTPacket_toString(printbuf, sizeof(printbuf), readbuf, len));
00397 #endif
00398     return rc;
00399 }
00400 
00401 
00402 // assume topic filter and name is in correct format
00403 // # can only be at end
00404 // + and # can only be next to separator
00405 template<class Network, class Timer, int a, int b>
00406 bool MQTT::Client<Network, Timer, a, b>::isTopicMatched(char* topicFilter, MQTTString& topicName)
00407 {
00408     char* curf = topicFilter;
00409     char* curn = topicName.lenstring.data;
00410     char* curn_end = curn + topicName.lenstring.len;
00411 
00412     while (*curf && curn < curn_end)
00413     {
00414         if (*curn == '/' && *curf != '/')
00415             break;
00416         if (*curf != '+' && *curf != '#' && *curf != *curn)
00417             break;
00418         if (*curf == '+')
00419         {   // skip until we meet the next separator, or end of string
00420             char* nextpos = curn + 1;
00421             while (nextpos < curn_end && *nextpos != '/')
00422                 nextpos = ++curn + 1;
00423         }
00424         else if (*curf == '#')
00425             curn = curn_end - 1;    // skip until end of string
00426         curf++;
00427         curn++;
00428     };
00429 
00430     return (curn == curn_end) && (*curf == '\0');
00431 }
00432 
00433 
00434 
00435 template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
00436 int MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::deliverMessage(MQTTString& topicName, Message& message)
00437 {
00438     int rc = FAILURE;
00439 
00440     // we have to find the right message handler - indexed by topic
00441     for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
00442     {
00443         if (messageHandlers[i].topicFilter != 0 && (MQTTPacket_equals(&topicName, (char*)messageHandlers[i].topicFilter) ||
00444                 isTopicMatched((char*)messageHandlers[i].topicFilter, topicName)))
00445         {
00446             if (messageHandlers[i].fp.attached())
00447             {
00448                 MessageData md(topicName, message);
00449                 messageHandlers[i].fp(md);
00450                 rc = SUCCESS;
00451             }
00452         }
00453     }
00454 
00455     if (rc == FAILURE && defaultMessageHandler.attached())
00456     {
00457         MessageData md(topicName, message);
00458         defaultMessageHandler(md);
00459         rc = SUCCESS;
00460     }
00461 
00462     return rc;
00463 }
00464 
00465 
00466 
00467 template<class Network, class Timer, int a, int b>
00468 int MQTT::Client<Network, Timer, a, b>::yield(unsigned long timeout_ms)
00469 {
00470     int rc = SUCCESS;
00471     Timer timer = Timer();
00472 
00473     timer.countdown_ms(timeout_ms);
00474     while (!timer.expired())
00475     {
00476         if (cycle(timer) == FAILURE)
00477         {
00478             rc = FAILURE;
00479             break;
00480         }
00481     }
00482 
00483     return rc;
00484 }
00485 
00486 
00487 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00488 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::cycle(Timer& timer)
00489 {
00490     /* get one piece of work off the wire and one pass through */
00491 
00492     // read the socket, see what work is due
00493     unsigned short packet_type = readPacket(timer);
00494 
00495     int len = 0,
00496         rc = SUCCESS;
00497 
00498     switch (packet_type)
00499     {
00500         case CONNACK:
00501         case PUBACK:
00502         case SUBACK:
00503             break;
00504         case PUBLISH:
00505             MQTTString topicName;
00506             Message msg;
00507             if (MQTTDeserialize_publish((unsigned char*)&msg.dup, (int*)&msg.qos, (unsigned char*)&msg.retained, (unsigned short*)&msg.id, &topicName,
00508                                  (unsigned char**)&msg.payload, (int*)&msg.payloadlen, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
00509                 goto exit;
00510 #if MQTTCLIENT_QOS2
00511             if (msg.qos != QOS2)
00512 #endif
00513                 deliverMessage(topicName, msg);
00514 #if MQTTCLIENT_QOS2
00515             else if (isQoS2msgidFree(msg.id))
00516             {
00517                 if (useQoS2msgid(msg.id))
00518                     deliverMessage(topicName, msg);
00519                 else
00520                     WARN("Maximum number of incoming QoS2 messages exceeded");
00521             }   
00522 #endif
00523 #if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
00524             if (msg.qos != QOS0)
00525             {
00526                 if (msg.qos == QOS1)
00527                     len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBACK, 0, msg.id);
00528                 else if (msg.qos == QOS2)
00529                     len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBREC, 0, msg.id);
00530                 if (len <= 0)
00531                     rc = FAILURE;
00532                 else
00533                     rc = sendPacket(len, timer);
00534                 if (rc == FAILURE)
00535                     goto exit; // there was a problem
00536             }
00537             break;
00538 #endif
00539 #if MQTTCLIENT_QOS2
00540         case PUBREC:
00541             unsigned short mypacketid;
00542             unsigned char dup, type;
00543             if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
00544                 rc = FAILURE;
00545             else if ((len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBREL, 0, mypacketid)) <= 0)
00546                 rc = FAILURE;
00547             else if ((rc = sendPacket(len, timer)) != SUCCESS) // send the PUBREL packet
00548                 rc = FAILURE; // there was a problem
00549             if (rc == FAILURE)
00550                 goto exit; // there was a problem
00551             break;
00552         case PUBCOMP:
00553             break;
00554 #endif
00555         case PINGRESP:
00556             ping_outstanding = false;
00557             break;
00558     }
00559     keepalive();
00560 exit:
00561     if (rc == SUCCESS)
00562         rc = packet_type;
00563     return rc;
00564 }
00565 
00566 
00567 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00568 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::keepalive()
00569 {
00570     int rc = FAILURE;
00571 
00572     if (keepAliveInterval == 0)
00573     {
00574         rc = SUCCESS;
00575         goto exit;
00576     }
00577 
00578     if (last_sent.expired() || last_received.expired())
00579     {
00580         if (!ping_outstanding)
00581         {
00582             Timer timer = Timer(1000);
00583             int len = MQTTSerialize_pingreq(sendbuf, MAX_MQTT_PACKET_SIZE);
00584             if (len > 0 && (rc = sendPacket(len, timer)) == SUCCESS) // send the ping packet
00585                 ping_outstanding = true;
00586         }
00587     }
00588 
00589 exit:
00590     return rc;
00591 }
00592 
00593 
00594 // only used in single-threaded mode where one command at a time is in process
00595 template<class Network, class Timer, int a, int b>
00596 int MQTT::Client<Network, Timer, a, b>::waitfor(int packet_type, Timer& timer)
00597 {
00598     int rc = FAILURE;
00599 
00600     do
00601     {
00602         if (timer.expired())
00603             break; // we timed out
00604     }
00605     while ((rc = cycle(timer)) != packet_type);
00606 
00607     return rc;
00608 }
00609 
00610 
00611 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00612 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::connect(MQTTPacket_connectData& options)
00613 {
00614     Timer connect_timer = Timer(command_timeout_ms);
00615     int rc = FAILURE;
00616     int len = 0;
00617 
00618     if (isconnected) // don't send connect packet again if we are already connected
00619         goto exit;
00620 
00621     this->keepAliveInterval = options.keepAliveInterval;
00622     this->cleansession = options.cleansession;
00623     if ((len = MQTTSerialize_connect(sendbuf, MAX_MQTT_PACKET_SIZE, &options)) <= 0)
00624         goto exit;
00625     if ((rc = sendPacket(len, connect_timer)) != SUCCESS)  // send the connect packet
00626         goto exit; // there was a problem
00627 
00628     if (this->keepAliveInterval > 0)
00629         last_received.countdown(this->keepAliveInterval);
00630     // this will be a blocking call, wait for the connack
00631     if (waitfor(CONNACK, connect_timer) == CONNACK)
00632     {
00633         unsigned char connack_rc = 255;
00634         bool sessionPresent = false;
00635         if (MQTTDeserialize_connack((unsigned char*)&sessionPresent, &connack_rc, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
00636             rc = connack_rc;
00637         else
00638             rc = FAILURE;
00639     }
00640     else
00641         rc = FAILURE;
00642         
00643 #if MQTTCLIENT_QOS2
00644     // resend an inflight publish
00645     if (inflightMsgid >0 && inflightQoS == QOS2 && pubrel)
00646     {
00647         if ((len = MQTTSerialize_ack(sendbuf, MAX_MQTT_PACKET_SIZE, PUBREL, 0, inflightMsgid)) <= 0)
00648             rc = FAILURE;
00649         else
00650             rc = publish(len, connect_timer, inflightQoS);
00651     }
00652     else
00653 #endif
00654 #if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
00655     if (inflightMsgid > 0)
00656     {
00657         memcpy(sendbuf, pubbuf, MAX_MQTT_PACKET_SIZE);
00658         rc = publish(inflightLen, connect_timer, inflightQoS);
00659     }
00660 #endif
00661 
00662 exit:
00663     if (rc == SUCCESS)
00664         isconnected = true;
00665     return rc;
00666 }
00667 
00668 
00669 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00670 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::connect()
00671 {
00672     MQTTPacket_connectData default_options = MQTTPacket_connectData_initializer;
00673     return connect(default_options);
00674 }
00675 
00676 
00677 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
00678 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::subscribe(const char* topicFilter, enum QoS qos, messageHandler messageHandler)
00679 {
00680     int rc = FAILURE;
00681     Timer timer = Timer(command_timeout_ms);
00682     int len = 0;
00683     MQTTString topic = {(char*)topicFilter, 0, 0};
00684 
00685     if (!isconnected)
00686         goto exit;
00687 
00688     len = MQTTSerialize_subscribe(sendbuf, MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic, (int*)&qos);
00689     if (len <= 0)
00690         goto exit;
00691     if ((rc = sendPacket(len, timer)) != SUCCESS) // send the subscribe packet
00692         goto exit;             // there was a problem
00693 
00694     if (waitfor(SUBACK, timer) == SUBACK)      // wait for suback
00695     {
00696         int count = 0, grantedQoS = -1;
00697         unsigned short mypacketid;
00698         if (MQTTDeserialize_suback(&mypacketid, 1, &count, &grantedQoS, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
00699             rc = grantedQoS; // 0, 1, 2 or 0x80
00700         if (rc != 0x80)
00701         {
00702             for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
00703             {
00704                 if (messageHandlers[i].topicFilter == 0)
00705                 {
00706                     messageHandlers[i].topicFilter = topicFilter;
00707                     messageHandlers[i].fp.attach(messageHandler);
00708                     rc = 0;
00709                     break;
00710                 }
00711             }
00712         }
00713     }
00714     else
00715         rc = FAILURE;
00716 
00717 exit:
00718     if (rc != SUCCESS)
00719         isconnected = false;
00720     return rc;
00721 }
00722 
00723 
00724 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
00725 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::unsubscribe(const char* topicFilter)
00726 {
00727     int rc = FAILURE;
00728     Timer timer = Timer(command_timeout_ms);
00729     MQTTString topic = {(char*)topicFilter, 0, 0};
00730     int len = 0;
00731 
00732     if (!isconnected)
00733         goto exit;
00734 
00735     if ((len = MQTTSerialize_unsubscribe(sendbuf, MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic)) <= 0)
00736         goto exit;
00737     if ((rc = sendPacket(len, timer)) != SUCCESS) // send the unsubscribe packet
00738         goto exit; // there was a problem
00739 
00740     if (waitfor(UNSUBACK, timer) == UNSUBACK)
00741     {
00742         unsigned short mypacketid;  // should be the same as the packetid above
00743         if (MQTTDeserialize_unsuback(&mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
00744             rc = 0;
00745     }
00746     else
00747         rc = FAILURE;
00748 
00749 exit:
00750     if (rc != SUCCESS)
00751         isconnected = false;
00752     return rc;
00753 }
00754 
00755 
00756 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00757 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::publish(int len, Timer& timer, enum QoS qos)
00758 {
00759     int rc;
00760     
00761     if ((rc = sendPacket(len, timer)) != SUCCESS) // send the publish packet
00762         goto exit; // there was a problem
00763 
00764 #if MQTTCLIENT_QOS1 
00765     if (qos == QOS1)
00766     {
00767         if (waitfor(PUBACK, timer) == PUBACK)
00768         {
00769             unsigned short mypacketid;
00770             unsigned char dup, type;
00771             if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
00772                 rc = FAILURE;
00773             else if (inflightMsgid == mypacketid)
00774                 inflightMsgid = 0;
00775         }
00776         else
00777             rc = FAILURE;
00778     }
00779 #elif MQTTCLIENT_QOS2
00780     else if (qos == QOS2)
00781     {
00782         if (waitfor(PUBCOMP, timer) == PUBCOMP)
00783         {
00784             unsigned short mypacketid;
00785             unsigned char dup, type;
00786             if (MQTTDeserialize_ack(&type, &dup, &mypacketid, readbuf, MAX_MQTT_PACKET_SIZE) != 1)
00787                 rc = FAILURE;
00788             else if (inflightMsgid == mypacketid)
00789                 inflightMsgid = 0;
00790         }
00791         else
00792             rc = FAILURE;
00793     }
00794 #endif
00795 
00796 exit:
00797     if (rc != SUCCESS)
00798         isconnected = false;
00799     return rc;
00800 }
00801 
00802 
00803 
00804 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00805 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)
00806 {
00807     int rc = FAILURE;
00808     Timer timer = Timer(command_timeout_ms);
00809     MQTTString topicString = MQTTString_initializer;
00810     int len = 0;
00811 
00812     if (!isconnected)
00813         goto exit;
00814         
00815     topicString.cstring = (char*)topicName;
00816 
00817 #if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
00818     if (qos == QOS1 || qos == QOS2)
00819         id = packetid.getNext();
00820 #endif
00821 
00822     len = MQTTSerialize_publish(sendbuf, MAX_MQTT_PACKET_SIZE, 0, qos, retained, id,
00823               topicString, (unsigned char*)payload, payloadlen);
00824     if (len <= 0)
00825         goto exit;
00826         
00827 #if MQTTCLIENT_QOS1 || MQTTCLIENT_QOS2
00828     if (!cleansession)
00829     {
00830         memcpy(pubbuf, sendbuf, len);
00831         inflightMsgid = id;
00832         inflightLen = len;
00833         inflightQoS = qos;
00834 #if MQTTCLIENT_QOS2
00835         pubrel = false;
00836 #endif
00837     }
00838 #endif
00839         
00840     rc = publish(len, timer, qos);
00841 exit:
00842     return rc;
00843 }
00844 
00845 
00846 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00847 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::publish(const char* topicName, void* payload, size_t payloadlen, enum QoS qos, bool retained)
00848 {
00849     unsigned short id = 0;  // dummy - not used for anything
00850     return publish(topicName, payload, payloadlen, id, qos, retained);
00851 }
00852 
00853 
00854 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00855 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::publish(const char* topicName, Message& message)
00856 {
00857     return publish(topicName, message.payload, message.payloadlen, message.qos, message.retained);
00858 }
00859 
00860 
00861 template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
00862 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::disconnect()
00863 {
00864     int rc = FAILURE;
00865     Timer timer = Timer(command_timeout_ms);     // we might wait for incomplete incoming publishes to complete
00866     int len = MQTTSerialize_disconnect(sendbuf, MAX_MQTT_PACKET_SIZE);
00867     if (len > 0)
00868         rc = sendPacket(len, timer);            // send the disconnect packet
00869 
00870     isconnected = false;
00871     return rc;
00872 }
00873 
00874 
00875 #endif