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 #if defined(__cplusplus) /* If this is a C++ compiler, use C linkage */
00022 extern "C" {
00023 #endif
00024 
00025 #if defined(WIN32_DLL) || defined(WIN64_DLL)
00026   #define DLLImport __declspec(dllimport)
00027   #define DLLExport __declspec(dllexport)
00028 #elif defined(LINUX_SO)
00029   #define DLLImport extern
00030   #define DLLExport  __attribute__ ((visibility ("default")))
00031 #else
00032   #define DLLImport
00033   #define DLLExport  
00034 #endif
00035 
00036 enum errors
00037 {
00038     MQTTPACKET_BUFFER_TOO_SHORT = -2,
00039     MQTTPACKET_READ_ERROR = -1,
00040     MQTTPACKET_READ_COMPLETE
00041 };
00042 
00043 enum msgTypes
00044 {
00045     CONNECT = 1, CONNACK, PUBLISH, PUBACK, PUBREC, PUBREL,
00046     PUBCOMP, SUBSCRIBE, SUBACK, UNSUBSCRIBE, UNSUBACK,
00047     PINGREQ, PINGRESP, DISCONNECT
00048 };
00049 
00050 /**
00051  * Bitfields for the MQTT header byte.
00052  */
00053 typedef union
00054 {
00055     unsigned char byte;                 /**< the whole byte */
00056 #if defined(REVERSED)
00057     struct
00058     {
00059         unsigned int type : 4;          /**< message type nibble */
00060         unsigned int dup : 1;               /**< DUP flag bit */
00061         unsigned int qos : 2;               /**< QoS value, 0, 1 or 2 */
00062         unsigned int retain : 1;        /**< retained flag bit */
00063     } bits;
00064 #else
00065     struct
00066     {
00067         unsigned int retain : 1;        /**< retained flag bit */
00068         unsigned int qos : 2;               /**< QoS value, 0, 1 or 2 */
00069         unsigned int dup : 1;               /**< DUP flag bit */
00070         unsigned int type : 4;          /**< message type nibble */
00071     } bits;
00072 #endif
00073 } MQTTHeader;
00074 
00075 typedef struct
00076 {
00077     int len;
00078     char* data;
00079 } MQTTLenString;
00080 
00081 typedef struct
00082 {
00083     char* cstring;
00084     MQTTLenString lenstring;
00085 } MQTTString;
00086 
00087 #define MQTTString_initializer {NULL, {0, NULL}}
00088 
00089 int MQTTstrlen(MQTTString mqttstring);
00090 
00091 #include "MQTTConnect.h"
00092 #include "MQTTPublish.h"
00093 #include "MQTTSubscribe.h"
00094 #include "MQTTUnsubscribe.h"
00095 #include "MQTTFormat.h"
00096 
00097 DLLExport int MQTTSerialize_ack(unsigned char* buf, int buflen, unsigned char type, unsigned char dup, unsigned short packetid);
00098 DLLExport int MQTTDeserialize_ack(unsigned char* packettype, unsigned char* dup, unsigned short* packetid, unsigned char* buf, int buflen);
00099 
00100 int MQTTPacket_len(int rem_len);
00101 DLLExport int MQTTPacket_equals(MQTTString* a, char* b);
00102 
00103 DLLExport int MQTTPacket_encode(unsigned char* buf, int length);
00104 int MQTTPacket_decode(int (*getcharfn)(unsigned char*, int), int* value);
00105 int MQTTPacket_decodeBuf(unsigned char* buf, int* value);
00106 
00107 int readInt(unsigned char** pptr);
00108 char readChar(unsigned char** pptr);
00109 void writeChar(unsigned char** pptr, char c);
00110 void writeInt(unsigned char** pptr, int anInt);
00111 int readMQTTLenString(MQTTString* mqttstring, unsigned char** pptr, unsigned char* enddata);
00112 void writeCString(unsigned char** pptr, const char* string);
00113 void writeMQTTString(unsigned char** pptr, MQTTString mqttstring);
00114 
00115 DLLExport int MQTTPacket_read(unsigned char* buf, int buflen, int (*getfn)(unsigned char*, int));
00116 
00117 typedef struct {
00118     int (*getfn)(void *, unsigned char*, int); /* must return -1 for error, 0 for call again, or the number of bytes read */
00119     void *sck;  /* pointer to whatever the system may use to identify the transport */
00120     int multiplier;
00121     int rem_len;
00122     int len;
00123     char state;
00124 }MQTTTransport;
00125 
00126 int MQTTPacket_readnb(unsigned char* buf, int buflen, MQTTTransport *trp);
00127 
00128 #ifdef __cplusplus /* If this is a C++ compiler, use C linkage */
00129 }
00130 #endif
00131 
00132 
00133 #endif /* MQTTPACKET_H_ */