DDD
Dependencies: HW4 FP MQTTPacket
Fork of MQTT by
MQTTClient.cpp
- Committer:
- icraggs
- Date:
- 2014-04-08
- Revision:
- 6:4d312a49200b
- Parent:
- 5:389ccac5a50c
- Child:
- 7:f9d690fb6dad
File content as of revision 6:4d312a49200b:
/******************************************************************************* * 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 "MQTTClient.h" #include "MQTTPacket.h" 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]; this->ipstack = ipstack; this->command_timeout = command_timeout; //this->thread = new Thread(0); // only need a background thread for non-blocking mode 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 PUBACK: break; case SUBACK: break; case PUBREC: break; case PUBCOMP: break; case PINGRESP: break; } return packet_type; } 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); 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 } 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; }