Ian Craggs / MQTTSNPacket

Low level MQTTSN packet library, part of the Eclipse Paho project: http://eclipse.org/paho

Dependents:   MQTTSN sara-n200-hello-mqtt-sn MQTTSN_2

The master source for this project is held at: https://github.com/eclipse/paho.mqtt-sn.embedded-c

MQTTSNDeserializePublish.c@0:c524a894b5e8, 2015-02-26 (annotated)

Committer:
icraggs
Date:
Thu Feb 26 15:59:36 2015 +0000
Revision:
0:c524a894b5e8
Child:
1:7fa362fa563f
First version that works nicely :-)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
icraggs 0:c524a894b5e8 1 /*******************************************************************************
icraggs 0:c524a894b5e8 2 * Copyright (c) 2014 IBM Corp.
icraggs 0:c524a894b5e8 3 *
icraggs 0:c524a894b5e8 4 * All rights reserved. This program and the accompanying materials
icraggs 0:c524a894b5e8 5 * are made available under the terms of the Eclipse Public License v1.0
icraggs 0:c524a894b5e8 6 * and Eclipse Distribution License v1.0 which accompany this distribution.
icraggs 0:c524a894b5e8 7 *
icraggs 0:c524a894b5e8 8 * The Eclipse Public License is available at
icraggs 0:c524a894b5e8 9 * http://www.eclipse.org/legal/epl-v10.html
icraggs 0:c524a894b5e8 10 * and the Eclipse Distribution License is available at
icraggs 0:c524a894b5e8 11 * http://www.eclipse.org/org/documents/edl-v10.php.
icraggs 0:c524a894b5e8 12 *
icraggs 0:c524a894b5e8 13 * Contributors:
icraggs 0:c524a894b5e8 14 * Ian Craggs - initial API and implementation and/or initial documentation
icraggs 0:c524a894b5e8 15 *******************************************************************************/
icraggs 0:c524a894b5e8 16
icraggs 0:c524a894b5e8 17 #include "StackTrace.h"
icraggs 0:c524a894b5e8 18 #include "MQTTSNPacket.h"
icraggs 0:c524a894b5e8 19 #include <string.h>
icraggs 0:c524a894b5e8 20
icraggs 0:c524a894b5e8 21 #define min(a, b) ((a < b) ? 1 : 0)
icraggs 0:c524a894b5e8 22
icraggs 0:c524a894b5e8 23 /**
icraggs 0:c524a894b5e8 24 * Deserializes the supplied (wire) buffer into publish data
icraggs 0:c524a894b5e8 25 * @param dup returned integer - the MQTT dup flag
icraggs 0:c524a894b5e8 26 * @param qos returned integer - the MQTT QoS value
icraggs 0:c524a894b5e8 27 * @param retained returned integer - the MQTT retained flag
icraggs 0:c524a894b5e8 28 * @param packetid returned integer - the MQTT packet identifier
icraggs 0:c524a894b5e8 29 * @param topicName returned MQTTSNString - the MQTT topic in the publish
icraggs 0:c524a894b5e8 30 * @param payload returned byte buffer - the MQTT publish payload
icraggs 0:c524a894b5e8 31 * @param payloadlen returned integer - the length of the MQTT payload
icraggs 0:c524a894b5e8 32 * @param buf the raw buffer data, of the correct length determined by the remaining length field
icraggs 0:c524a894b5e8 33 * @param buflen the length in bytes of the data in the supplied buffer
icraggs 0:c524a894b5e8 34 * @return error code. 1 is success
icraggs 0:c524a894b5e8 35 */
icraggs 0:c524a894b5e8 36 int MQTTSNDeserialize_publish(unsigned char* dup, int* qos, unsigned char* retained, unsigned short* packetid, MQTTSN_topicid* topic,
icraggs 0:c524a894b5e8 37 unsigned char** payload, int* payloadlen, unsigned char* buf, int buflen)
icraggs 0:c524a894b5e8 38 {
icraggs 0:c524a894b5e8 39 MQTTSNFlags flags;
icraggs 0:c524a894b5e8 40 unsigned char* curdata = buf;
icraggs 0:c524a894b5e8 41 unsigned char* enddata = NULL;
icraggs 0:c524a894b5e8 42 int rc = 0;
icraggs 0:c524a894b5e8 43 int mylen = 0;
icraggs 0:c524a894b5e8 44
icraggs 0:c524a894b5e8 45 FUNC_ENTRY;
icraggs 0:c524a894b5e8 46 curdata += (rc = MQTTSNPacket_decode(curdata, buflen, &mylen)); /* read length */
icraggs 0:c524a894b5e8 47 enddata = buf + mylen;
icraggs 0:c524a894b5e8 48 if (enddata - curdata > buflen)
icraggs 0:c524a894b5e8 49 goto exit;
icraggs 0:c524a894b5e8 50
icraggs 0:c524a894b5e8 51 if (readChar(&curdata) != MQTTSN_PUBLISH)
icraggs 0:c524a894b5e8 52 goto exit;
icraggs 0:c524a894b5e8 53
icraggs 0:c524a894b5e8 54 flags.all = readChar(&curdata);
icraggs 0:c524a894b5e8 55 *dup = flags.bits.dup;
icraggs 0:c524a894b5e8 56 *qos = flags.bits.QoS;
icraggs 0:c524a894b5e8 57 *retained = flags.bits.retain;
icraggs 0:c524a894b5e8 58
icraggs 0:c524a894b5e8 59 topic->type = flags.bits.topicIdType;
icraggs 0:c524a894b5e8 60 if (topic->type == MQTTSN_TOPIC_TYPE_NORMAL && *qos == 3)
icraggs 0:c524a894b5e8 61 {
icraggs 0:c524a894b5e8 62 /* special arrangement for long topic names in QoS -1 publishes. The length of the topic is in the topicid field */
icraggs 0:c524a894b5e8 63 topic->data.long_.len = readInt(&curdata);
icraggs 0:c524a894b5e8 64 }
icraggs 0:c524a894b5e8 65 else if (topic->type == MQTTSN_TOPIC_TYPE_NORMAL || topic->type == MQTTSN_TOPIC_TYPE_PREDEFINED)
icraggs 0:c524a894b5e8 66 topic->data.id = readInt(&curdata);
icraggs 0:c524a894b5e8 67 else
icraggs 0:c524a894b5e8 68 {
icraggs 0:c524a894b5e8 69 topic->data.short_name[0] = readChar(&curdata);
icraggs 0:c524a894b5e8 70 topic->data.short_name[1] = readChar(&curdata);
icraggs 0:c524a894b5e8 71 }
icraggs 0:c524a894b5e8 72 *packetid = readInt(&curdata);
icraggs 0:c524a894b5e8 73
icraggs 0:c524a894b5e8 74 if (topic->type == MQTTSN_TOPIC_TYPE_NORMAL && *qos == 3)
icraggs 0:c524a894b5e8 75 {
icraggs 0:c524a894b5e8 76 topic->data.long_.name = (char*)curdata;
icraggs 0:c524a894b5e8 77 curdata += topic->data.long_.len;
icraggs 0:c524a894b5e8 78 }
icraggs 0:c524a894b5e8 79
icraggs 0:c524a894b5e8 80 *payloadlen = enddata - curdata;
icraggs 0:c524a894b5e8 81 *payload = curdata;
icraggs 0:c524a894b5e8 82 rc = 1;
icraggs 0:c524a894b5e8 83 exit:
icraggs 0:c524a894b5e8 84 FUNC_EXIT_RC(rc);
icraggs 0:c524a894b5e8 85 return rc;
icraggs 0:c524a894b5e8 86 }
icraggs 0:c524a894b5e8 87
icraggs 0:c524a894b5e8 88
icraggs 0:c524a894b5e8 89 int MQTTSNDeserialize_puback(unsigned short* topicid, unsigned short* packetid,
icraggs 0:c524a894b5e8 90 unsigned char* returncode, unsigned char* buf, int buflen)
icraggs 0:c524a894b5e8 91 {
icraggs 0:c524a894b5e8 92 unsigned char* curdata = buf;
icraggs 0:c524a894b5e8 93 unsigned char* enddata = NULL;
icraggs 0:c524a894b5e8 94 int rc = 0;
icraggs 0:c524a894b5e8 95 int mylen = 0;
icraggs 0:c524a894b5e8 96
icraggs 0:c524a894b5e8 97 FUNC_ENTRY;
icraggs 0:c524a894b5e8 98 curdata += (rc = MQTTSNPacket_decode(curdata, buflen, &mylen)); /* read length */
icraggs 0:c524a894b5e8 99 enddata = buf + mylen;
icraggs 0:c524a894b5e8 100 if (enddata - curdata > buflen)
icraggs 0:c524a894b5e8 101 goto exit;
icraggs 0:c524a894b5e8 102
icraggs 0:c524a894b5e8 103 if (readChar(&curdata) != MQTTSN_PUBACK)
icraggs 0:c524a894b5e8 104 goto exit;
icraggs 0:c524a894b5e8 105
icraggs 0:c524a894b5e8 106 *topicid = readInt(&curdata);
icraggs 0:c524a894b5e8 107 *packetid = readInt(&curdata);
icraggs 0:c524a894b5e8 108 *returncode = readChar(&curdata);
icraggs 0:c524a894b5e8 109
icraggs 0:c524a894b5e8 110 rc = 1;
icraggs 0:c524a894b5e8 111 exit:
icraggs 0:c524a894b5e8 112 FUNC_EXIT_RC(rc);
icraggs 0:c524a894b5e8 113 return rc;
icraggs 0:c524a894b5e8 114 }
icraggs 0:c524a894b5e8 115
icraggs 0:c524a894b5e8 116
icraggs 0:c524a894b5e8 117 /**
icraggs 0:c524a894b5e8 118 * Deserializes the supplied (wire) buffer into an ack
icraggs 0:c524a894b5e8 119 * @param packettype returned integer - the MQTT packet type
icraggs 0:c524a894b5e8 120 * @param packetid returned integer - the MQTT packet identifier
icraggs 0:c524a894b5e8 121 * @param buf the raw buffer data, of the correct length determined by the remaining length field
icraggs 0:c524a894b5e8 122 * @param buflen the length in bytes of the data in the supplied buffer
icraggs 0:c524a894b5e8 123 * @return error code. 1 is success, 0 is failure
icraggs 0:c524a894b5e8 124 */
icraggs 0:c524a894b5e8 125 int MQTTSNDeserialize_ack(unsigned char* type, unsigned short* packetid, unsigned char* buf, int buflen)
icraggs 0:c524a894b5e8 126 {
icraggs 0:c524a894b5e8 127 unsigned char* curdata = buf;
icraggs 0:c524a894b5e8 128 unsigned char* enddata = NULL;
icraggs 0:c524a894b5e8 129 int rc = 0;
icraggs 0:c524a894b5e8 130 int mylen = 0;
icraggs 0:c524a894b5e8 131
icraggs 0:c524a894b5e8 132 FUNC_ENTRY;
icraggs 0:c524a894b5e8 133 curdata += (rc = MQTTSNPacket_decode(curdata, buflen, &mylen)); /* read length */
icraggs 0:c524a894b5e8 134 enddata = buf + mylen;
icraggs 0:c524a894b5e8 135 if (enddata - curdata > buflen)
icraggs 0:c524a894b5e8 136 goto exit;
icraggs 0:c524a894b5e8 137
icraggs 0:c524a894b5e8 138 *type = readChar(&curdata);
icraggs 0:c524a894b5e8 139 if (*type != MQTTSN_PUBREL && *type != MQTTSN_PUBREC && *type != MQTTSN_PUBCOMP)
icraggs 0:c524a894b5e8 140 goto exit;
icraggs 0:c524a894b5e8 141
icraggs 0:c524a894b5e8 142 *packetid = readInt(&curdata);
icraggs 0:c524a894b5e8 143
icraggs 0:c524a894b5e8 144 rc = 1;
icraggs 0:c524a894b5e8 145 exit:
icraggs 0:c524a894b5e8 146 FUNC_EXIT_RC(rc);
icraggs 0:c524a894b5e8 147 return rc;
icraggs 0:c524a894b5e8 148 }
icraggs 0:c524a894b5e8 149
icraggs 0:c524a894b5e8 150
icraggs 0:c524a894b5e8 151 /**
icraggs 0:c524a894b5e8 152 * Deserializes the supplied (wire) buffer into register data
icraggs 0:c524a894b5e8 153 * @param topicid returned topic id
icraggs 0:c524a894b5e8 154 * @param packetid returned integer - the MQTT packet identifier
icraggs 0:c524a894b5e8 155 * @param topicName returned MQTTSNString - the MQTT topic in the register
icraggs 0:c524a894b5e8 156 * @param buf the raw buffer data, of the correct length determined by the remaining length field
icraggs 0:c524a894b5e8 157 * @param buflen the length in bytes of the data in the supplied buffer
icraggs 0:c524a894b5e8 158 * @return error code. 1 is success
icraggs 0:c524a894b5e8 159 */
icraggs 0:c524a894b5e8 160 int MQTTSNDeserialize_register(unsigned short* topicid, unsigned short* packetid, MQTTSNString* topicname,
icraggs 0:c524a894b5e8 161 unsigned char* buf, int buflen)
icraggs 0:c524a894b5e8 162 {
icraggs 0:c524a894b5e8 163 unsigned char* curdata = buf;
icraggs 0:c524a894b5e8 164 unsigned char* enddata = NULL;
icraggs 0:c524a894b5e8 165 int rc = 0;
icraggs 0:c524a894b5e8 166 int mylen = 0;
icraggs 0:c524a894b5e8 167
icraggs 0:c524a894b5e8 168 FUNC_ENTRY;
icraggs 0:c524a894b5e8 169 curdata += (rc = MQTTSNPacket_decode(curdata, buflen, &mylen)); /* read length */
icraggs 0:c524a894b5e8 170 enddata = buf + mylen;
icraggs 0:c524a894b5e8 171 if (enddata - curdata > buflen)
icraggs 0:c524a894b5e8 172 goto exit;
icraggs 0:c524a894b5e8 173
icraggs 0:c524a894b5e8 174 if (readChar(&curdata) != MQTTSN_REGISTER)
icraggs 0:c524a894b5e8 175 goto exit;
icraggs 0:c524a894b5e8 176
icraggs 0:c524a894b5e8 177 *topicid = readInt(&curdata);
icraggs 0:c524a894b5e8 178 *packetid = readInt(&curdata);
icraggs 0:c524a894b5e8 179
icraggs 0:c524a894b5e8 180 topicname->lenstring.data = (char*)curdata;
icraggs 0:c524a894b5e8 181 topicname->lenstring.len = enddata - curdata;
icraggs 0:c524a894b5e8 182 topicname->cstring = NULL;
icraggs 0:c524a894b5e8 183
icraggs 0:c524a894b5e8 184 rc = 1;
icraggs 0:c524a894b5e8 185 exit:
icraggs 0:c524a894b5e8 186 FUNC_EXIT_RC(rc);
icraggs 0:c524a894b5e8 187 return rc;
icraggs 0:c524a894b5e8 188 }
icraggs 0:c524a894b5e8 189
icraggs 0:c524a894b5e8 190
icraggs 0:c524a894b5e8 191 /**
icraggs 0:c524a894b5e8 192 * Deserializes the supplied (wire) buffer into register data
icraggs 0:c524a894b5e8 193 * @param topicid returned topic id
icraggs 0:c524a894b5e8 194 * @param packetid returned integer - the MQTT packet identifier
icraggs 0:c524a894b5e8 195 * @param return_code returned integer return code
icraggs 0:c524a894b5e8 196 * @param buf the raw buffer data, of the correct length determined by the remaining length field
icraggs 0:c524a894b5e8 197 * @param buflen the length in bytes of the data in the supplied buffer
icraggs 0:c524a894b5e8 198 * @return error code. 1 is success
icraggs 0:c524a894b5e8 199 */
icraggs 0:c524a894b5e8 200 int MQTTSNDeserialize_regack(unsigned short* topicid, unsigned short* packetid, unsigned char* return_code,
icraggs 0:c524a894b5e8 201 unsigned char* buf, int buflen)
icraggs 0:c524a894b5e8 202 {
icraggs 0:c524a894b5e8 203 unsigned char* curdata = buf;
icraggs 0:c524a894b5e8 204 unsigned char* enddata = NULL;
icraggs 0:c524a894b5e8 205 int rc = 0;
icraggs 0:c524a894b5e8 206 int mylen = 0;
icraggs 0:c524a894b5e8 207
icraggs 0:c524a894b5e8 208 FUNC_ENTRY;
icraggs 0:c524a894b5e8 209 curdata += (rc = MQTTSNPacket_decode(curdata, buflen, &mylen)); /* read length */
icraggs 0:c524a894b5e8 210 enddata = buf + mylen;
icraggs 0:c524a894b5e8 211 if (enddata - curdata > buflen)
icraggs 0:c524a894b5e8 212 goto exit;
icraggs 0:c524a894b5e8 213
icraggs 0:c524a894b5e8 214 if (readChar(&curdata) != MQTTSN_REGACK)
icraggs 0:c524a894b5e8 215 goto exit;
icraggs 0:c524a894b5e8 216
icraggs 0:c524a894b5e8 217 *topicid = readInt(&curdata);
icraggs 0:c524a894b5e8 218 *packetid = readInt(&curdata);
icraggs 0:c524a894b5e8 219 *return_code = readChar(&curdata);
icraggs 0:c524a894b5e8 220
icraggs 0:c524a894b5e8 221 rc = 1;
icraggs 0:c524a894b5e8 222 exit:
icraggs 0:c524a894b5e8 223 FUNC_EXIT_RC(rc);
icraggs 0:c524a894b5e8 224 return rc;
icraggs 0:c524a894b5e8 225 }
icraggs 0:c524a894b5e8 226