MQTTPacket.h

00001 /*******************************************************************************
00002  * Copyright (c) 2014 IBM Corp.
00003  *
00004  * All rights reserved. This program and the accompanying materials
00005  * are made available under the terms of the Eclipse Public License v1.0
00006  * and Eclipse Distribution License v1.0 which accompany this distribution.
00007  *
00008  * The Eclipse Public License is available at
00009  *    http://www.eclipse.org/legal/epl-v10.html
00010  * and the Eclipse Distribution License is available at
00011  *   http://www.eclipse.org/org/documents/edl-v10.php.
00012  *
00013  * Contributors:
00014  *    Ian Craggs - initial API and implementation and/or initial documentation
00015  *    Xiang Rong - 442039 Add makefile to Embedded C client
00016  *******************************************************************************/
00017 
00018 #ifndef MQTTPACKET_H_
00019 #define MQTTPACKET_H_
00020 
00021 #include <stddef.h>
00022 
00023 #if defined(__cplusplus) /* If this is a C++ compiler, use C linkage */
00024 extern "C" {
00025 #endif
00026 
00027 #if defined(WIN32_DLL) || defined(WIN64_DLL)
00028   #define DLLImport __declspec(dllimport)
00029   #define DLLExport __declspec(dllexport)
00030 #elif defined(LINUX_SO)
00031   #define DLLImport extern
00032   #define DLLExport  __attribute__ ((visibility ("default")))
00033 #else
00034   #define DLLImport
00035   #define DLLExport  
00036 #endif
00037 
00038 enum errors
00039 {
00040     MQTTPACKET_BUFFER_TOO_SHORT = -2,
00041     MQTTPACKET_READ_ERROR = -1,
00042     MQTTPACKET_READ_COMPLETE
00043 };
00044 
00045 enum msgTypes
00046 {
00047     CONNECT_MSG = 1, CONNACK_MSG, PUBLISH_MSG, PUBACK_MSG, PUBREC_MSG, PUBREL_MSG,
00048     PUBCOMP_MSG, SUBSCRIBE_MSG, SUBACK_MSG, UNSUBSCRIBE_MSG, UNSUBACK_MSG,
00049     PINGREQ_MSG, PINGRESP_MSG, DISCONNECT_MSG
00050 };
00051 
00052 /**
00053  * Bitfields for the MQTT header byte.
00054  */
00055 typedef union
00056 {
00057     unsigned char byte;                 /**< the whole byte */
00058 #if defined(REVERSED)
00059     struct
00060     {
00061         unsigned int type : 4;          /**< message type nibble */
00062         unsigned int dup : 1;               /**< DUP flag bit */
00063         unsigned int qos : 2;               /**< QoS value, 0, 1 or 2 */
00064         unsigned int retain : 1;        /**< retained flag bit */
00065     } bits;
00066 #else
00067     struct
00068     {
00069         unsigned int retain : 1;        /**< retained flag bit */
00070         unsigned int qos : 2;               /**< QoS value, 0, 1 or 2 */
00071         unsigned int dup : 1;               /**< DUP flag bit */
00072         unsigned int type : 4;          /**< message type nibble */
00073     } bits;
00074 #endif
00075 } MQTTHeader;
00076 
00077 typedef struct
00078 {
00079     size_t len;
00080     char* data;
00081 } MQTTLenString;
00082 
00083 typedef struct
00084 {
00085     char* cstring;
00086     MQTTLenString lenstring;
00087 } MQTTString;
00088 
00089 #define MQTTString_initializer {NULL, {0, NULL}}
00090 
00091 size_t MQTTstrlen(MQTTString mqttstring);
00092 
00093 #include "MQTTConnect.h"
00094 #include "MQTTPublish.h"
00095 #include "MQTTSubscribe.h"
00096 #include "MQTTUnsubscribe.h"
00097 
00098 int MQTTSerialize_ack(unsigned char* buf, size_t buflen, unsigned char type, unsigned char dup, unsigned short packetid);
00099 int MQTTDeserialize_ack(unsigned char* packettype, unsigned char* dup, unsigned short* packetid, unsigned char* buf, size_t buflen);
00100 
00101 size_t MQTTPacket_len(size_t rem_len);
00102 int MQTTPacket_equals(MQTTString* a, char* b);
00103 
00104 int MQTTPacket_encode(unsigned char* buf, size_t length);
00105 int MQTTPacket_decode(int (*getcharfn)(unsigned char*, int), int* value);
00106 int MQTTPacket_decodeBuf(unsigned char* buf, int* value);
00107 
00108 int readInt(unsigned char** pptr);
00109 char readChar(unsigned char** pptr);
00110 void writeChar(unsigned char** pptr, char c);
00111 void writeInt(unsigned char** pptr, int anInt);
00112 int readMQTTLenString(MQTTString* mqttstring, unsigned char** pptr, unsigned char* enddata);
00113 void writeCString(unsigned char** pptr, const char* string);
00114 void writeMQTTString(unsigned char** pptr, MQTTString mqttstring);
00115 
00116 DLLExport int MQTTPacket_read(unsigned char* buf, int buflen, int (*getfn)(unsigned char*, int));
00117 
00118 typedef struct {
00119     int (*getfn)(void *, unsigned char*, int); /* must return -1 for error, 0 for call again, or the number of bytes read */
00120     void *sck;  /* pointer to whatever the system may use to identify the transport */
00121     int multiplier;
00122     int rem_len;
00123     int len;
00124     char state;
00125 }MQTTTransport;
00126 
00127 int MQTTPacket_readnb(unsigned char* buf, int buflen, MQTTTransport *trp);
00128 
00129 #ifdef __cplusplus /* If this is a C++ compiler, use C linkage */
00130 }
00131 #endif
00132 
00133 
00134 #endif /* MQTTPACKET_H_ */