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Diff: MQTTSNDeserializePublish.c
- Revision:
- 0:c524a894b5e8
- Child:
- 1:7fa362fa563f
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MQTTSNDeserializePublish.c Thu Feb 26 15:59:36 2015 +0000 @@ -0,0 +1,226 @@ +/******************************************************************************* + * 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> + +#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 MQTTSNString - 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 MQTTSNDeserialize_publish(unsigned char* dup, int* qos, unsigned char* retained, unsigned short* packetid, MQTTSN_topicid* topic, + unsigned char** payload, int* payloadlen, unsigned char* buf, int buflen) +{ + MQTTSNFlags flags; + 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 (readChar(&curdata) != MQTTSN_PUBLISH) + goto exit; + + flags.all = readChar(&curdata); + *dup = flags.bits.dup; + *qos = flags.bits.QoS; + *retained = flags.bits.retain; + + topic->type = flags.bits.topicIdType; + if (topic->type == MQTTSN_TOPIC_TYPE_NORMAL && *qos == 3) + { + /* special arrangement for long topic names in QoS -1 publishes. The length of the topic is in the topicid field */ + topic->data.long_.len = readInt(&curdata); + } + else if (topic->type == MQTTSN_TOPIC_TYPE_NORMAL || topic->type == MQTTSN_TOPIC_TYPE_PREDEFINED) + topic->data.id = readInt(&curdata); + else + { + topic->data.short_name[0] = readChar(&curdata); + topic->data.short_name[1] = readChar(&curdata); + } + *packetid = readInt(&curdata); + + if (topic->type == MQTTSN_TOPIC_TYPE_NORMAL && *qos == 3) + { + topic->data.long_.name = (char*)curdata; + curdata += topic->data.long_.len; + } + + *payloadlen = enddata - curdata; + *payload = curdata; + rc = 1; +exit: + FUNC_EXIT_RC(rc); + return rc; +} + + +int MQTTSNDeserialize_puback(unsigned short* topicid, unsigned short* packetid, + unsigned char* returncode, unsigned char* buf, int buflen) +{ + 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 (readChar(&curdata) != MQTTSN_PUBACK) + goto exit; + + *topicid = readInt(&curdata); + *packetid = readInt(&curdata); + *returncode = readChar(&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 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 MQTTSNDeserialize_ack(unsigned char* type, unsigned short* packetid, unsigned char* buf, int buflen) +{ + 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; + + *type = readChar(&curdata); + if (*type != MQTTSN_PUBREL && *type != MQTTSN_PUBREC && *type != MQTTSN_PUBCOMP) + goto exit; + + *packetid = readInt(&curdata); + + rc = 1; +exit: + FUNC_EXIT_RC(rc); + return rc; +} + + +/** + * Deserializes the supplied (wire) buffer into register data + * @param topicid returned topic id + * @param packetid returned integer - the MQTT packet identifier + * @param topicName returned MQTTSNString - the MQTT topic in the register + * @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_register(unsigned short* topicid, unsigned short* packetid, MQTTSNString* topicname, + unsigned char* buf, int buflen) +{ + 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 (readChar(&curdata) != MQTTSN_REGISTER) + goto exit; + + *topicid = readInt(&curdata); + *packetid = readInt(&curdata); + + topicname->lenstring.data = (char*)curdata; + topicname->lenstring.len = enddata - curdata; + topicname->cstring = NULL; + + rc = 1; +exit: + FUNC_EXIT_RC(rc); + return rc; +} + + +/** + * Deserializes the supplied (wire) buffer into register data + * @param topicid returned topic id + * @param packetid returned integer - the MQTT packet identifier + * @param return_code returned integer return code + * @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_regack(unsigned short* topicid, unsigned short* packetid, unsigned char* return_code, + unsigned char* buf, int buflen) +{ + 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 (readChar(&curdata) != MQTTSN_REGACK) + goto exit; + + *topicid = readInt(&curdata); + *packetid = readInt(&curdata); + *return_code = readChar(&curdata); + + rc = 1; +exit: + FUNC_EXIT_RC(rc); + return rc; +} +