Diff: MQTTClient.h

Revision:

8:c46930bd6c82

Parent:

6:4d312a49200b

Child:

9:01b8cc7d94cc

--- a/MQTTClient.h	Wed Apr 09 11:37:28 2014 +0100
+++ b/MQTTClient.h	Wed Apr 09 13:48:20 2014 +0000
@@ -66,6 +66,8 @@
     
     int disconnect(int timeout, FP<void, Result*> *resultHandler = 0);
     
+    void run(void const *argument);
+    
 private:
 
     int getPacketId();
@@ -91,6 +93,213 @@
     
 };
 
+void threadfn(void* arg);
+
+}
+
+template<class Network, class Timer, class Thread> MQTT::Client<Network, Timer, Thread>::Client(Network* network, Timer* timer, const int buffer_size, const int command_timeout)
+{
+    
+   buf = new char[buffer_size];
+   readbuf = new char[buffer_size];
+   buflen = readbuflen = buffer_size;
+   this->command_timeout = command_timeout;
+   this->thread = 0;
+   this->ipstack = network;
+   this->packetid = 0;
+   this->timer = timer;
+}
+
+
+template<class Network, class Timer, class Thread> int MQTT::Client<Network, Timer, Thread>::getPacketId()
+{
+    return this->packetid = (this->packetid == MAX_PACKET_ID) ? 1 : ++this->packetid;
+}
+
+
+template<class Network, class Timer, class Thread> int MQTT::Client<Network, Timer, Thread>::sendPacket(int length, int timeout)
+{
+    int sent = 0;
+    
+    while (sent < length)
+        sent += ipstack->write(&buf[sent], length, -1);
+        
+    return sent;
+}
+
+
+template<class Network, class Timer, class Thread> int MQTT::Client<Network, Timer, Thread>::decodePacket(int* value, int timeout)
+{
+    char c;
+    int multiplier = 1;
+    int len = 0;
+#define 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> int MQTT::Client<Network, Timer, Thread>::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> int MQTT::Client<Network, Timer, Thread>::cycle()
+{
+    int timeout = 1000L;
+    /* get one piece of work off the wire and one pass through */
+    
+    // 1. read the socket, see what work is due. 
+    int packet_type = readPacket(-1);
+
+    printf("packet type %d\n", packet_type);
+    
+    switch (packet_type)
+    {
+        case CONNACK:
+            printf("connack received\n");
+            break;
+        case PUBLISH:
+            break;
+        case PUBACK:
+            break;
+        case SUBACK:
+            break;
+        case PUBREC:
+            break;
+        case PUBCOMP:
+            break;
+        case PINGRESP:
+            break;
+        case -1:
+            break;
+    }
+    return packet_type;
+}
+
+
+template<class Network, class Timer, class Thread> void MQTT::Client<Network, Timer, Thread>::run(void const *argument)
+{
+}
+
+
+template<class Network, class Timer, class Thread> int MQTT::Client<Network, Timer, Thread>::connect(MQTTPacket_connectData* options, FP<void, MQTT::Result*> *resultHandler)
+{
+    int len = 0;
+    int rc = -99;
+    MQTTPacket_connectData default_options = MQTTPacket_connectData_initializer;
+
+    /* 2. if the connect was successful, send the MQTT connect packet */   
+    if (options == 0)
+    {
+        default_options.clientID.cstring = "me";
+        options = &default_options;
+    }
+    
+    this->keepalive = options->keepAliveInterval;
+    len = MQTTSerialize_connect(buf, buflen, options);
+    printf("len from send is %d %d\n", len, buflen);
+    rc = sendPacket(len); // send the connect packet
+    printf("rc from send is %d\n", rc);
+    
+    /* 3. wait until the connack is received */
+    if (resultHandler == 0)
+    {
+        // this will be a blocking call, wait for the connack
+        if (cycle() == CONNACK)
+        {
+            int connack_rc = -1;
+            if (MQTTDeserialize_connack(&connack_rc, readbuf, readbuflen) == 1)
+                rc = connack_rc;
+        }
+    }
+    else
+    {
+        // set connect response callback function
+        
+        // start background thread
+            
+        this->thread = new Thread((void (*)(void const *argument))&MQTT::threadfn, (void*)this);
+    }
+    
+    return rc;
+}
+
+
+template<class Network, class Timer, class Thread> int MQTT::Client<Network, Timer, Thread>::subscribe(const char* topicFilter, enum QoS qos, FP<void, Message*> messageHandler, 
+        FP<void, Result*> *resultHandler)
+{
+    int rc = -1, 
+        len = 0;
+    MQTTString topic = {(char*)topicFilter, 0, 0};
+    
+    len = MQTTSerialize_subscribe(buf, buflen, 0, getPacketId(), 1, &topic, (int*)&qos);
+    rc = sendPacket(len); // send the subscribe packet
+    
+    /* wait for suback */
+    if (resultHandler == 0)
+    {
+        // this will block
+        if (cycle() == SUBACK)
+        {
+            int count = 0, grantedQoS = -1;
+            if (MQTTDeserialize_suback(&packetid, 1, &count, &grantedQoS, readbuf, readbuflen) == 1)
+                rc = grantedQoS; // 0, 1, 2 or 0x80 
+        }
+    }
+    else
+    {
+        // set subscribe response callback function
+        
+    }
+    
+    return rc;
+}
+
+
 #endif