123
MQTTSNSubscribeServer.c
- Committer:
- m_ahsan
- Date:
- 2019-01-03
- Revision:
- 2:573d544b5d3c
- Parent:
- 1:7fa362fa563f
File content as of revision 2:573d544b5d3c:
/******************************************************************************* * 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 "MQTTSNPacket.h" #include <string.h> /** * Deserializes the supplied (wire) buffer into subscribe data * @param dup the returned MQTT-SN dup flag * @param qos the returned qos * @param packetid returned - the same value as the one contained in the corresponding SUBSCRIBE * @param topicFilter returned - the topic filter - normal, predefined or short * @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 MQTTSNDeserialize_subscribe(unsigned char* dup, int* qos, unsigned short* packetid, MQTTSN_topicid* topicFilter, unsigned char* buf, int buflen) { MQTTSNFlags flags = {0}; unsigned char* curdata = buf; unsigned char* enddata = NULL; int rc = 0; int mylen = 0; FUNC_ENTRY; curdata += (rc = MQTTSNPacket_decode(curdata, buflen, &mylen)); /* read length */ enddata = buf + mylen; if (enddata - curdata > buflen) goto exit; if (MQTTSNPacket_readChar(&curdata) != MQTTSN_SUBSCRIBE) goto exit; flags.all = MQTTSNPacket_readChar(&curdata); *dup = flags.bits.dup; *qos = flags.bits.QoS; *packetid = MQTTSNPacket_readInt(&curdata); topicFilter->type = flags.bits.topicIdType; if (topicFilter->type == MQTTSN_TOPIC_TYPE_NORMAL) { topicFilter->data.long_.len = enddata - curdata; topicFilter->data.long_.name = (char*)curdata; } else if (topicFilter->type == MQTTSN_TOPIC_TYPE_PREDEFINED) topicFilter->data.id = MQTTSNPacket_readInt(&curdata); else if (topicFilter->type == MQTTSN_TOPIC_TYPE_SHORT) { topicFilter->data.short_name[0] = MQTTSNPacket_readChar(&curdata); topicFilter->data.short_name[1] = MQTTSNPacket_readChar(&curdata); } 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 qos integer - the MQTT-SN QoS value * @param topicid if "accepted" the value which will be used by the gateway in subsequent PUBLISH packets * @param packetid integer - the MQTT-SN packet identifier * @param returncode returned - "accepted" or rejection reason * @return the length of the serialized data. <= 0 indicates error */ int MQTTSNSerialize_suback(unsigned char* buf, int buflen, int qos, unsigned short topicid, unsigned short packetid, unsigned char returncode) { MQTTSNFlags flags = {0}; unsigned char *ptr = buf; int len = 0; int rc = 0; FUNC_ENTRY; if ((len = MQTTSNPacket_len(7)) > buflen) { rc = MQTTSNPACKET_BUFFER_TOO_SHORT; goto exit; } ptr += MQTTSNPacket_encode(ptr, len); /* write length */ MQTTSNPacket_writeChar(&ptr, MQTTSN_SUBACK); /* write message type */ flags.all = 0; flags.bits.QoS = qos; MQTTSNPacket_writeChar(&ptr, flags.all); MQTTSNPacket_writeInt(&ptr, topicid); MQTTSNPacket_writeInt(&ptr, packetid); MQTTSNPacket_writeChar(&ptr, returncode); rc = ptr - buf; exit: FUNC_EXIT_RC(rc); return rc; }