stm32大项目阶段20251015

1.ubuntu配置mqtt步骤

1.1先进入ubuntu的家目录中，把paho.mqtt.c-1.3.0.tar.gz软件复制到家目录中

1.2解压mqtt库资料

sudo tar -vxf paho.mqtt.c-1.3.0.tar.gz

1.3解压得到的如下的文件夹

1.4进入到paho.mqtt.c-1.3.0/install目录下

paho.mqtt.c-1.3.0/install

1.5把 include 中所有文件拷贝到/usr/include 目录中

sudo cp include/* /usr/include

1.6把 lib 中所有内容拷贝到/usr/lib 目录中即可在代码中直接引用。拷贝命令如下：

sudo cp -d lib/*so* /usr/lib

必须增加-d 选项，保持软链接属性

1.7ubuntu中安装如下软件，添加32位兼容库：

sudo apt install gcc-multilib g++-multilib

2.MQTT客户端

免费的公共 MQTT 服务器 | EMQ (emqx.com)
 

https://www.emqx.com/zh/mqtt/public-mqtt5-broker

2.1MQTT代码

cJSON.c

/*Copyright (c) 2009 Dave GamblePermission is hereby granted, free of charge, to any person obtaining a copyof this software and associated documentation files (the "Software"), to dealin the Software without restriction, including without limitation the rightsto use, copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom the Software isfurnished to do so, subject to the following conditions:The above copyright notice and this permission notice shall be included inall copies or substantial portions of the Software.THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THEAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHERLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS INTHE SOFTWARE.
*//* cJSON */
/* JSON parser in C. */#include <string.h>
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <float.h>
#include <limits.h>
#include <ctype.h>
#include "cJSON.h"static const char *ep;const char *cJSON_GetErrorPtr(void) {return ep;}
//
static int cJSON_strcasecmp(const char *s1,const char *s2)
{if (!s1) return (s1==s2)?0:1;if (!s2) return 1;for(; tolower(*s1) == tolower(*s2); ++s1, ++s2)	if(*s1 == 0)	return 0;return tolower(*(const unsigned char *)s1) - tolower(*(const unsigned char *)s2);
}static void *(*cJSON_malloc)(size_t sz) = malloc;
static void (*cJSON_free)(void *ptr) = free;static char* cJSON_strdup(const char* str)
{size_t len;char* copy;len = strlen(str) + 1;if (!(copy = (char*)cJSON_malloc(len))) return 0;memcpy(copy,str,len);return copy;
}void cJSON_InitHooks(cJSON_Hooks* hooks)
{if (!hooks) { /* Reset hooks */cJSON_malloc = malloc;cJSON_free = free;return;}cJSON_malloc = (hooks->malloc_fn)?hooks->malloc_fn:malloc;cJSON_free	 = (hooks->free_fn)?hooks->free_fn:free;
}/* Internal constructor. */
static cJSON *cJSON_New_Item(void)
{cJSON* node = (cJSON*)cJSON_malloc(sizeof(cJSON));if (node) memset(node,0,sizeof(cJSON));return node;
}/* Delete a cJSON structure. */
void cJSON_Delete(cJSON *c)
{cJSON *next;while (c){next=c->next;if (!(c->type&cJSON_IsReference) && c->child) cJSON_Delete(c->child);if (!(c->type&cJSON_IsReference) && c->valuestring) cJSON_free(c->valuestring);if (!(c->type&cJSON_StringIsConst) && c->string) cJSON_free(c->string);cJSON_free(c);c=next;}
}/* Parse the input text to generate a number, and populate the result into item. */
static const char *parse_number(cJSON *item,const char *num)
{double n=0,sign=1,scale=0;int subscale=0,signsubscale=1;if (*num=='-') sign=-1,num++;	/* Has sign? */if (*num=='0') num++;			/* is zero */if (*num>='1' && *num<='9')	do	n=(n*10.0)+(*num++ -'0');	while (*num>='0' && *num<='9');	/* Number? */if (*num=='.' && num[1]>='0' && num[1]<='9') {num++;		do	n=(n*10.0)+(*num++ -'0'),scale--; while (*num>='0' && *num<='9');}	/* Fractional part? */if (*num=='e' || *num=='E')		/* Exponent? */{	num++;if (*num=='+') num++;	else if (*num=='-') signsubscale=-1,num++;		/* With sign? */while (*num>='0' && *num<='9') subscale=(subscale*10)+(*num++ - '0');	/* Number? */}n=sign*n*pow(10.0,(scale+subscale*signsubscale));	/* number = +/- number.fraction * 10^+/- exponent */item->valuedouble=n;item->valueint=(int)n;item->type=cJSON_Number;return num;
}static int pow2gt (int x)	{	--x;	x|=x>>1;	x|=x>>2;	x|=x>>4;	x|=x>>8;	x|=x>>16;	return x+1;	}typedef struct {char *buffer; int length; int offset; } printbuffer;static char* ensure(printbuffer *p,int needed)
{char *newbuffer;int newsize;if (!p || !p->buffer) return 0;needed+=p->offset;if (needed<=p->length) return p->buffer+p->offset;newsize=pow2gt(needed);newbuffer=(char*)cJSON_malloc(newsize);if (!newbuffer) {cJSON_free(p->buffer);p->length=0,p->buffer=0;return 0;}if (newbuffer) memcpy(newbuffer,p->buffer,p->length);cJSON_free(p->buffer);p->length=newsize;p->buffer=newbuffer;return newbuffer+p->offset;
}static int update(printbuffer *p)
{char *str;if (!p || !p->buffer) return 0;str=p->buffer+p->offset;return p->offset+strlen(str);
}/* Render the number nicely from the given item into a string. */
static char *print_number(cJSON *item,printbuffer *p)
{char *str=0;double d=item->valuedouble;if (d==0){if (p)	str=ensure(p,2);else	str=(char*)cJSON_malloc(2);	/* special case for 0. */if (str) strcpy(str,"0");}else if (fabs(((double)item->valueint)-d)<=DBL_EPSILON && d<=INT_MAX && d>=INT_MIN){if (p)	str=ensure(p,21);else	str=(char*)cJSON_malloc(21);	/* 2^64+1 can be represented in 21 chars. */if (str)	sprintf(str,"%d",item->valueint);}else{if (p)	str=ensure(p,64);else	str=(char*)cJSON_malloc(64);	/* This is a nice tradeoff. */if (str){if (fpclassify(d) != FP_ZERO && !isnormal(d))				sprintf(str,"null");else if (fabs(floor(d)-d)<=DBL_EPSILON && fabs(d)<1.0e60)	sprintf(str,"%.0f",d);else if (fabs(d)<1.0e-6 || fabs(d)>1.0e9)					sprintf(str,"%e",d);else														sprintf(str,"%f",d);}}return str;
}static unsigned parse_hex4(const char *str)
{unsigned h=0;if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;h=h<<4;str++;if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;h=h<<4;str++;if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;h=h<<4;str++;if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;return h;
}/* Parse the input text into an unescaped cstring, and populate item. */
static const unsigned char firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
static const char *parse_string(cJSON *item,const char *str)
{const char *ptr=str+1;char *ptr2;char *out;int len=0;unsigned uc,uc2;if (*str!='\"') {ep=str;return 0;}	/* not a string! */while (*ptr!='\"' && *ptr && ++len) if (*ptr++ == '\\') ptr++;	/* Skip escaped quotes. */out=(char*)cJSON_malloc(len+1);	/* This is how long we need for the string, roughly. */if (!out) return 0;ptr=str+1;ptr2=out;while (*ptr!='\"' && *ptr){if (*ptr!='\\') *ptr2++=*ptr++;else{ptr++;switch (*ptr){case 'b': *ptr2++='\b';	break;case 'f': *ptr2++='\f';	break;case 'n': *ptr2++='\n';	break;case 'r': *ptr2++='\r';	break;case 't': *ptr2++='\t';	break;case 'u':	 /* transcode utf16 to utf8. */uc=parse_hex4(ptr+1);ptr+=4;	/* get the unicode char. */if ((uc>=0xDC00 && uc<=0xDFFF) || uc==0)	break;	/* check for invalid.	*/if (uc>=0xD800 && uc<=0xDBFF)	/* UTF16 surrogate pairs.	*/{if (ptr[1]!='\\' || ptr[2]!='u')	break;	/* missing second-half of surrogate.	*/uc2=parse_hex4(ptr+3);ptr+=6;if (uc2<0xDC00 || uc2>0xDFFF)		break;	/* invalid second-half of surrogate.	*/uc=0x10000 + (((uc&0x3FF)<<10) | (uc2&0x3FF));}len=4;if (uc<0x80) len=1;else if (uc<0x800) len=2;else if (uc<0x10000) len=3; ptr2+=len;switch (len) {case 4: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;case 3: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;case 2: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;case 1: *--ptr2 =(uc | firstByteMark[len]);}ptr2+=len;break;default:  *ptr2++=*ptr; break;}ptr++;}}*ptr2=0;if (*ptr=='\"') ptr++;item->valuestring=out;item->type=cJSON_String;return ptr;
}/* Render the cstring provided to an escaped version that can be printed. */
static char *print_string_ptr(const char *str,printbuffer *p)
{const char *ptr;char *ptr2,*out;int len=0,flag=0;unsigned char token;for (ptr=str;*ptr;ptr++) flag|=((*ptr>0 && *ptr<32)||(*ptr=='\"')||(*ptr=='\\'))?1:0;if (!flag){len=ptr-str;if (p) out=ensure(p,len+3);else		out=(char*)cJSON_malloc(len+3);if (!out) return 0;ptr2=out;*ptr2++='\"';strcpy(ptr2,str);ptr2[len]='\"';ptr2[len+1]=0;return out;}if (!str){if (p)	out=ensure(p,3);else	out=(char*)cJSON_malloc(3);if (!out) return 0;strcpy(out,"\"\"");return out;}ptr=str;while ((token=*ptr) && ++len) {if (strchr("\"\\\b\f\n\r\t",token)) len++; else if (token<32) len+=5;ptr++;}if (p)	out=ensure(p,len+3);else	out=(char*)cJSON_malloc(len+3);if (!out) return 0;ptr2=out;ptr=str;*ptr2++='\"';while (*ptr){if ((unsigned char)*ptr>31 && *ptr!='\"' && *ptr!='\\') *ptr2++=*ptr++;else{*ptr2++='\\';switch (token=*ptr++){case '\\':	*ptr2++='\\';	break;case '\"':	*ptr2++='\"';	break;case '\b':	*ptr2++='b';	break;case '\f':	*ptr2++='f';	break;case '\n':	*ptr2++='n';	break;case '\r':	*ptr2++='r';	break;case '\t':	*ptr2++='t';	break;default: sprintf(ptr2,"u%04x",token);ptr2+=5;	break;	/* escape and print */}}}*ptr2++='\"';*ptr2++=0;return out;
}
/* Invote print_string_ptr (which is useful) on an item. */
static char *print_string(cJSON *item,printbuffer *p)	{return print_string_ptr(item->valuestring,p);}/* Predeclare these prototypes. */
static const char *parse_value(cJSON *item,const char *value);
static char *print_value(cJSON *item,int depth,int fmt,printbuffer *p);
static const char *parse_array(cJSON *item,const char *value);
static char *print_array(cJSON *item,int depth,int fmt,printbuffer *p);
static const char *parse_object(cJSON *item,const char *value);
static char *print_object(cJSON *item,int depth,int fmt,printbuffer *p);/* Utility to jump whitespace and cr/lf */
static const char *skip(const char *in) {while (in && *in && (unsigned char)*in<=32) in++; return in;}/* Parse an object - create a new root, and populate. */
cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated)
{const char *end=0;cJSON *c=cJSON_New_Item();ep=0;if (!c) return 0;       /* memory fail */end=parse_value(c,skip(value));if (!end)	{cJSON_Delete(c);return 0;}	/* parse failure. ep is set. *//* if we require null-terminated JSON without appended garbage, skip and then check for a null terminator */if (require_null_terminated) {end=skip(end);if (*end) {cJSON_Delete(c);ep=end;return 0;}}if (return_parse_end) *return_parse_end=end;return c;
}
/* Default options for cJSON_Parse */
cJSON *cJSON_Parse(const char *value) {return cJSON_ParseWithOpts(value,0,0);}/* Render a cJSON item/entity/structure to text. */
char *cJSON_Print(cJSON *item)				{return print_value(item,0,1,0);}
char *cJSON_PrintUnformatted(cJSON *item)	{return print_value(item,0,0,0);}char *cJSON_PrintBuffered(cJSON *item,int prebuffer,int fmt)
{printbuffer p;p.buffer=(char*)cJSON_malloc(prebuffer);p.length=prebuffer;p.offset=0;return print_value(item,0,fmt,&p);return p.buffer;
}/* Parser core - when encountering text, process appropriately. */
static const char *parse_value(cJSON *item,const char *value)
{if (!value)						return 0;	/* Fail on null. */if (!strncmp(value,"null",4))	{ item->type=cJSON_NULL;  return value+4; }if (!strncmp(value,"false",5))	{ item->type=cJSON_False; return value+5; }if (!strncmp(value,"true",4))	{ item->type=cJSON_True; item->valueint=1;	return value+4; }if (*value=='\"')				{ return parse_string(item,value); }if (*value=='-' || (*value>='0' && *value<='9'))	{ return parse_number(item,value); }if (*value=='[')				{ return parse_array(item,value); }if (*value=='{')				{ return parse_object(item,value); }ep=value;return 0;	/* failure. */
}/* Render a value to text. */
static char *print_value(cJSON *item,int depth,int fmt,printbuffer *p)
{char *out=0;if (!item) return 0;if (p){switch ((item->type)&255){case cJSON_NULL:	{out=ensure(p,5);	if (out) strcpy(out,"null");	break;}case cJSON_False:	{out=ensure(p,6);	if (out) strcpy(out,"false");	break;}case cJSON_True:	{out=ensure(p,5);	if (out) strcpy(out,"true");	break;}case cJSON_Number:	out=print_number(item,p);break;case cJSON_String:	out=print_string(item,p);break;case cJSON_Array:	out=print_array(item,depth,fmt,p);break;case cJSON_Object:	out=print_object(item,depth,fmt,p);break;}}else{switch ((item->type)&255){case cJSON_NULL:	out=cJSON_strdup("null");	break;case cJSON_False:	out=cJSON_strdup("false");break;case cJSON_True:	out=cJSON_strdup("true"); break;case cJSON_Number:	out=print_number(item,0);break;case cJSON_String:	out=print_string(item,0);break;case cJSON_Array:	out=print_array(item,depth,fmt,0);break;case cJSON_Object:	out=print_object(item,depth,fmt,0);break;}}return out;
}/* Build an array from input text. */
static const char *parse_array(cJSON *item,const char *value)
{cJSON *child;if (*value!='[')	{ep=value;return 0;}	/* not an array! */item->type=cJSON_Array;value=skip(value+1);if (*value==']') return value+1;	/* empty array. */item->child=child=cJSON_New_Item();if (!item->child) return 0;		 /* memory fail */value=skip(parse_value(child,skip(value)));	/* skip any spacing, get the value. */if (!value) return 0;while (*value==','){cJSON *new_item;if (!(new_item=cJSON_New_Item())) return 0; 	/* memory fail */child->next=new_item;new_item->prev=child;child=new_item;value=skip(parse_value(child,skip(value+1)));if (!value) return 0;	/* memory fail */}if (*value==']') return value+1;	/* end of array */ep=value;return 0;	/* malformed. */
}/* Render an array to text */
static char *print_array(cJSON *item,int depth,int fmt,printbuffer *p)
{char **entries;char *out=0,*ptr,*ret;int len=5;cJSON *child=item->child;int numentries=0,i=0,fail=0;size_t tmplen=0;/* How many entries in the array? */while (child) numentries++,child=child->next;/* Explicitly handle numentries==0 */if (!numentries){if (p)	out=ensure(p,3);else	out=(char*)cJSON_malloc(3);if (out) strcpy(out,"[]");return out;}if (p){/* Compose the output array. */i=p->offset;ptr=ensure(p,1);if (!ptr) return 0;	*ptr='[';	p->offset++;child=item->child;while (child && !fail){print_value(child,depth+1,fmt,p);p->offset=update(p);if (child->next) {len=fmt?2:1;ptr=ensure(p,len+1);if (!ptr) return 0;*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;p->offset+=len;}child=child->next;}ptr=ensure(p,2);if (!ptr) return 0;	*ptr++=']';*ptr=0;out=(p->buffer)+i;}else{/* Allocate an array to hold the values for each */entries=(char**)cJSON_malloc(numentries*sizeof(char*));if (!entries) return 0;memset(entries,0,numentries*sizeof(char*));/* Retrieve all the results: */child=item->child;while (child && !fail){ret=print_value(child,depth+1,fmt,0);entries[i++]=ret;if (ret) len+=strlen(ret)+2+(fmt?1:0); else fail=1;child=child->next;}/* If we didn't fail, try to malloc the output string */if (!fail)	out=(char*)cJSON_malloc(len);/* If that fails, we fail. */if (!out) fail=1;/* Handle failure. */if (fail){for (i=0;i<numentries;i++) if (entries[i]) cJSON_free(entries[i]);cJSON_free(entries);return 0;}/* Compose the output array. */*out='[';ptr=out+1;*ptr=0;for (i=0;i<numentries;i++){tmplen=strlen(entries[i]);memcpy(ptr,entries[i],tmplen);ptr+=tmplen;if (i!=numentries-1) {*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;}cJSON_free(entries[i]);}cJSON_free(entries);*ptr++=']';*ptr++=0;}return out;	
}/* Build an object from the text. */
static const char *parse_object(cJSON *item,const char *value)
{cJSON *child;if (*value!='{')	{ep=value;return 0;}	/* not an object! */item->type=cJSON_Object;value=skip(value+1);if (*value=='}') return value+1;	/* empty array. */item->child=child=cJSON_New_Item();if (!item->child) return 0;value=skip(parse_string(child,skip(value)));if (!value) return 0;child->string=child->valuestring;child->valuestring=0;if (*value!=':') {ep=value;return 0;}	/* fail! */value=skip(parse_value(child,skip(value+1)));	/* skip any spacing, get the value. */if (!value) return 0;while (*value==','){cJSON *new_item;if (!(new_item=cJSON_New_Item()))	return 0; /* memory fail */child->next=new_item;new_item->prev=child;child=new_item;value=skip(parse_string(child,skip(value+1)));if (!value) return 0;child->string=child->valuestring;child->valuestring=0;if (*value!=':') {ep=value;return 0;}	/* fail! */value=skip(parse_value(child,skip(value+1)));	/* skip any spacing, get the value. */if (!value) return 0;}if (*value=='}') return value+1;	/* end of array */ep=value;return 0;	/* malformed. */
}/* Render an object to text. */
static char *print_object(cJSON *item,int depth,int fmt,printbuffer *p)
{char **entries=0,**names=0;char *out=0,*ptr,*ret,*str;int len=7,i=0,j;cJSON *child=item->child;int numentries=0,fail=0;size_t tmplen=0;/* Count the number of entries. */while (child) numentries++,child=child->next;/* Explicitly handle empty object case */if (!numentries){if (p) out=ensure(p,fmt?depth+4:3);else	out=(char*)cJSON_malloc(fmt?depth+4:3);if (!out)	return 0;ptr=out;*ptr++='{';if (fmt) {*ptr++='\n';for (i=0;i<depth-1;i++) *ptr++='\t';}*ptr++='}';*ptr++=0;return out;}if (p){/* Compose the output: */i=p->offset;len=fmt?2:1;	ptr=ensure(p,len+1);	if (!ptr) return 0;*ptr++='{';	if (fmt) *ptr++='\n';	*ptr=0;	p->offset+=len;child=item->child;depth++;while (child){if (fmt){ptr=ensure(p,depth);	if (!ptr) return 0;for (j=0;j<depth;j++) *ptr++='\t';p->offset+=depth;}print_string_ptr(child->string,p);p->offset=update(p);len=fmt?2:1;ptr=ensure(p,len);	if (!ptr) return 0;*ptr++=':';if (fmt) *ptr++='\t';p->offset+=len;print_value(child,depth,fmt,p);p->offset=update(p);len=(fmt?1:0)+(child->next?1:0);ptr=ensure(p,len+1); if (!ptr) return 0;if (child->next) *ptr++=',';if (fmt) *ptr++='\n';*ptr=0;p->offset+=len;child=child->next;}ptr=ensure(p,fmt?(depth+1):2);	 if (!ptr) return 0;if (fmt)	for (i=0;i<depth-1;i++) *ptr++='\t';*ptr++='}';*ptr=0;out=(p->buffer)+i;}else{/* Allocate space for the names and the objects */entries=(char**)cJSON_malloc(numentries*sizeof(char*));if (!entries) return 0;names=(char**)cJSON_malloc(numentries*sizeof(char*));if (!names) {cJSON_free(entries);return 0;}memset(entries,0,sizeof(char*)*numentries);memset(names,0,sizeof(char*)*numentries);/* Collect all the results into our arrays: */child=item->child;depth++;if (fmt) len+=depth;while (child && !fail){names[i]=str=print_string_ptr(child->string,0);entries[i++]=ret=print_value(child,depth,fmt,0);if (str && ret) len+=strlen(ret)+strlen(str)+2+(fmt?2+depth:0); else fail=1;child=child->next;}/* Try to allocate the output string */if (!fail)	out=(char*)cJSON_malloc(len);if (!out) fail=1;/* Handle failure */if (fail){for (i=0;i<numentries;i++) {if (names[i]) cJSON_free(names[i]);if (entries[i]) cJSON_free(entries[i]);}cJSON_free(names);cJSON_free(entries);return 0;}/* Compose the output: */*out='{';ptr=out+1;if (fmt)*ptr++='\n';*ptr=0;for (i=0;i<numentries;i++){if (fmt) for (j=0;j<depth;j++) *ptr++='\t';tmplen=strlen(names[i]);memcpy(ptr,names[i],tmplen);ptr+=tmplen;*ptr++=':';if (fmt) *ptr++='\t';strcpy(ptr,entries[i]);ptr+=strlen(entries[i]);if (i!=numentries-1) *ptr++=',';if (fmt) *ptr++='\n';*ptr=0;cJSON_free(names[i]);cJSON_free(entries[i]);}cJSON_free(names);cJSON_free(entries);if (fmt) for (i=0;i<depth-1;i++) *ptr++='\t';*ptr++='}';*ptr++=0;}return out;	
}/* Get Array size/item / object item. */
int    cJSON_GetArraySize(cJSON *array)							{cJSON *c=array->child;int i=0;while(c)i++,c=c->next;return i;}
cJSON *cJSON_GetArrayItem(cJSON *array,int item)				{cJSON *c=array->child;  while (c && item>0) item--,c=c->next; return c;}
cJSON *cJSON_GetObjectItem(cJSON *object,const char *string)	{cJSON *c=object->child; while (c && cJSON_strcasecmp(c->string,string)) c=c->next; return c;}
int cJSON_HasObjectItem(cJSON *object,const char *string)	{cJSON *c=object->child;while (c ){if(cJSON_strcasecmp(c->string,string)==0){return 1;}c=c->next;}return 0;
}/* Utility for array list handling. */
static void suffix_object(cJSON *prev,cJSON *item) {prev->next=item;item->prev=prev;}
/* Utility for handling references. */
static cJSON *create_reference(cJSON *item) {cJSON *ref=cJSON_New_Item();if (!ref) return 0;memcpy(ref,item,sizeof(cJSON));ref->string=0;ref->type|=cJSON_IsReference;ref->next=ref->prev=0;return ref;}/* Add item to array/object. */
void   cJSON_AddItemToArray(cJSON *array, cJSON *item)						{cJSON *c=array->child;if (!item) return; if (!c) {array->child=item;} else {while (c && c->next) c=c->next; suffix_object(c,item);}}
void   cJSON_AddItemToObject(cJSON *object,const char *string,cJSON *item)	{if (!item) return; if (item->string) cJSON_free(item->string);item->string=cJSON_strdup(string);cJSON_AddItemToArray(object,item);}
void   cJSON_AddItemToObjectCS(cJSON *object,const char *string,cJSON *item)	{if (!item) return; if (!(item->type&cJSON_StringIsConst) && item->string) cJSON_free(item->string);item->string=(char*)string;item->type|=cJSON_StringIsConst;cJSON_AddItemToArray(object,item);}
void	cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item)						{cJSON_AddItemToArray(array,create_reference(item));}
void	cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item)	{cJSON_AddItemToObject(object,string,create_reference(item));}cJSON *cJSON_DetachItemFromArray(cJSON *array,int which)			{cJSON *c=array->child;while (c && which>0) c=c->next,which--;if (!c) return 0;if (c->prev) c->prev->next=c->next;if (c->next) c->next->prev=c->prev;if (c==array->child) array->child=c->next;c->prev=c->next=0;return c;}
void   cJSON_DeleteItemFromArray(cJSON *array,int which)			{cJSON_Delete(cJSON_DetachItemFromArray(array,which));}
cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string) {int i=0;cJSON *c=object->child;while (c && cJSON_strcasecmp(c->string,string)) i++,c=c->next;if (c) return cJSON_DetachItemFromArray(object,i);return 0;}
void   cJSON_DeleteItemFromObject(cJSON *object,const char *string) {cJSON_Delete(cJSON_DetachItemFromObject(object,string));}/* Replace array/object items with new ones. */
void   cJSON_InsertItemInArray(cJSON *array,int which,cJSON *newitem)		{cJSON *c=array->child;while (c && which>0) c=c->next,which--;if (!c) {cJSON_AddItemToArray(array,newitem);return;}newitem->next=c;newitem->prev=c->prev;c->prev=newitem;if (c==array->child) array->child=newitem; else newitem->prev->next=newitem;}
void   cJSON_ReplaceItemInArray(cJSON *array,int which,cJSON *newitem)		{cJSON *c=array->child;while (c && which>0) c=c->next,which--;if (!c) return;newitem->next=c->next;newitem->prev=c->prev;if (newitem->next) newitem->next->prev=newitem;if (c==array->child) array->child=newitem; else newitem->prev->next=newitem;c->next=c->prev=0;cJSON_Delete(c);}
void   cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem){int i=0;cJSON *c=object->child;while(c && cJSON_strcasecmp(c->string,string))i++,c=c->next;if(c){newitem->string=cJSON_strdup(string);cJSON_ReplaceItemInArray(object,i,newitem);}}/* Create basic types: */
cJSON *cJSON_CreateNull(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_NULL;return item;}
cJSON *cJSON_CreateTrue(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_True;return item;}
cJSON *cJSON_CreateFalse(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_False;return item;}
cJSON *cJSON_CreateBool(int b)					{cJSON *item=cJSON_New_Item();if(item)item->type=b?cJSON_True:cJSON_False;return item;}
cJSON *cJSON_CreateNumber(double num)			{cJSON *item=cJSON_New_Item();if(item){item->type=cJSON_Number;item->valuedouble=num;item->valueint=(int)num;}return item;}
cJSON *cJSON_CreateString(const char *string)	{cJSON *item=cJSON_New_Item();if(item){item->type=cJSON_String;item->valuestring=cJSON_strdup(string);}return item;}
cJSON *cJSON_CreateArray(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_Array;return item;}
cJSON *cJSON_CreateObject(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_Object;return item;}/* Create Arrays: */
cJSON *cJSON_CreateIntArray(const int *numbers,int count)		{int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateNumber(numbers[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;}
cJSON *cJSON_CreateFloatArray(const float *numbers,int count)	{int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateNumber(numbers[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;}
cJSON *cJSON_CreateDoubleArray(const double *numbers,int count)	{int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateNumber(numbers[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;}
cJSON *cJSON_CreateStringArray(const char **strings,int count)	{int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateString(strings[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;}/* Duplication */
cJSON *cJSON_Duplicate(cJSON *item,int recurse)
{cJSON *newitem,*cptr,*nptr=0,*newchild;/* Bail on bad ptr */if (!item) return 0;/* Create new item */newitem=cJSON_New_Item();if (!newitem) return 0;/* Copy over all vars */newitem->type=item->type&(~cJSON_IsReference),newitem->valueint=item->valueint,newitem->valuedouble=item->valuedouble;if (item->valuestring)	{newitem->valuestring=cJSON_strdup(item->valuestring);	if (!newitem->valuestring)	{cJSON_Delete(newitem);return 0;}}if (item->string)		{newitem->string=cJSON_strdup(item->string);			if (!newitem->string)		{cJSON_Delete(newitem);return 0;}}/* If non-recursive, then we're done! */if (!recurse) return newitem;/* Walk the ->next chain for the child. */cptr=item->child;while (cptr){newchild=cJSON_Duplicate(cptr,1);		/* Duplicate (with recurse) each item in the ->next chain */if (!newchild) {cJSON_Delete(newitem);return 0;}if (nptr)	{nptr->next=newchild,newchild->prev=nptr;nptr=newchild;}	/* If newitem->child already set, then crosswire ->prev and ->next and move on */else		{newitem->child=newchild;nptr=newchild;}					/* Set newitem->child and move to it */cptr=cptr->next;}return newitem;
}void cJSON_Minify(char *json)
{char *into=json;while (*json){if (*json==' ') json++;else if (*json=='\t') json++;	/* Whitespace characters. */else if (*json=='\r') json++;else if (*json=='\n') json++;else if (*json=='/' && json[1]=='/')  while (*json && *json!='\n') json++;	/* double-slash comments, to end of line. */else if (*json=='/' && json[1]=='*') {while (*json && !(*json=='*' && json[1]=='/')) json++;json+=2;}	/* multiline comments. */else if (*json=='\"'){*into++=*json++;while (*json && *json!='\"'){if (*json=='\\') *into++=*json++;*into++=*json++;}*into++=*json++;} /* string literals, which are \" sensitive. */else *into++=*json++;			/* All other characters. */}*into=0;	/* and null-terminate. */
}

cJSON.h

/*Copyright (c) 2009 Dave GamblePermission is hereby granted, free of charge, to any person obtaining a copyof this software and associated documentation files (the "Software"), to dealin the Software without restriction, including without limitation the rightsto use, copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom the Software isfurnished to do so, subject to the following conditions:The above copyright notice and this permission notice shall be included inall copies or substantial portions of the Software.THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THEAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHERLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS INTHE SOFTWARE.
*/#ifndef cJSON__h
#define cJSON__h#include <stddef.h>#ifdef __cplusplus
extern "C"
{
#endif/* cJSON Types: */
#define cJSON_False 0
#define cJSON_True 1
#define cJSON_NULL 2
#define cJSON_Number 3
#define cJSON_String 4
#define cJSON_Array 5
#define cJSON_Object 6#define cJSON_IsReference 256
#define cJSON_StringIsConst 512/* The cJSON structure: */
typedef struct cJSON {struct cJSON *next,*prev;	/* next/prev allow you to walk array/object chains. Alternatively, use GetArraySize/GetArrayItem/GetObjectItem */struct cJSON *child;		/* An array or object item will have a child pointer pointing to a chain of the items in the array/object. */int type;					/* The type of the item, as above. */char *valuestring;			/* The item's string, if type==cJSON_String */int valueint;				/* The item's number, if type==cJSON_Number */double valuedouble;			/* The item's number, if type==cJSON_Number */char *string;				/* The item's name string, if this item is the child of, or is in the list of subitems of an object. */
} cJSON;typedef struct cJSON_Hooks {void *(*malloc_fn)(size_t sz);void (*free_fn)(void *ptr);
} cJSON_Hooks;/* Supply malloc, realloc and free functions to cJSON */
extern void cJSON_InitHooks(cJSON_Hooks* hooks);/* Supply a block of JSON, and this returns a cJSON object you can interrogate. Call cJSON_Delete when finished. */
extern cJSON *cJSON_Parse(const char *value);
/* Render a cJSON entity to text for transfer/storage. Free the char* when finished. */
extern char  *cJSON_Print(cJSON *item);
/* Render a cJSON entity to text for transfer/storage without any formatting. Free the char* when finished. */
extern char  *cJSON_PrintUnformatted(cJSON *item);
/* Render a cJSON entity to text using a buffered strategy. prebuffer is a guess at the final size. guessing well reduces reallocation. fmt=0 gives unformatted, =1 gives formatted */
extern char *cJSON_PrintBuffered(cJSON *item,int prebuffer,int fmt);
/* Delete a cJSON entity and all subentities. */
extern void   cJSON_Delete(cJSON *c);/* Returns the number of items in an array (or object). */
extern int	  cJSON_GetArraySize(cJSON *array);
/* Retrieve item number "item" from array "array". Returns NULL if unsuccessful. */
extern cJSON *cJSON_GetArrayItem(cJSON *array,int item);
/* Get item "string" from object. Case insensitive. */
extern cJSON *cJSON_GetObjectItem(cJSON *object,const char *string);
extern int cJSON_HasObjectItem(cJSON *object,const char *string);
/* For analysing failed parses. This returns a pointer to the parse error. You'll probably need to look a few chars back to make sense of it. Defined when cJSON_Parse() returns 0. 0 when cJSON_Parse() succeeds. */
extern const char *cJSON_GetErrorPtr(void);/* These calls create a cJSON item of the appropriate type. */
extern cJSON *cJSON_CreateNull(void);
extern cJSON *cJSON_CreateTrue(void);
extern cJSON *cJSON_CreateFalse(void);
extern cJSON *cJSON_CreateBool(int b);
extern cJSON *cJSON_CreateNumber(double num);
extern cJSON *cJSON_CreateString(const char *string);
extern cJSON *cJSON_CreateArray(void);
extern cJSON *cJSON_CreateObject(void);/* These utilities create an Array of count items. */
extern cJSON *cJSON_CreateIntArray(const int *numbers,int count);
extern cJSON *cJSON_CreateFloatArray(const float *numbers,int count);
extern cJSON *cJSON_CreateDoubleArray(const double *numbers,int count);
extern cJSON *cJSON_CreateStringArray(const char **strings,int count);/* Append item to the specified array/object. */
extern void cJSON_AddItemToArray(cJSON *array, cJSON *item);
extern void	cJSON_AddItemToObject(cJSON *object,const char *string,cJSON *item);
extern void	cJSON_AddItemToObjectCS(cJSON *object,const char *string,cJSON *item);	/* Use this when string is definitely const (i.e. a literal, or as good as), and will definitely survive the cJSON object */
/* Append reference to item to the specified array/object. Use this when you want to add an existing cJSON to a new cJSON, but don't want to corrupt your existing cJSON. */
extern void cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item);
extern void	cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item);/* Remove/Detatch items from Arrays/Objects. */
extern cJSON *cJSON_DetachItemFromArray(cJSON *array,int which);
extern void   cJSON_DeleteItemFromArray(cJSON *array,int which);
extern cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string);
extern void   cJSON_DeleteItemFromObject(cJSON *object,const char *string);/* Update array items. */
extern void cJSON_InsertItemInArray(cJSON *array,int which,cJSON *newitem);	/* Shifts pre-existing items to the right. */
extern void cJSON_ReplaceItemInArray(cJSON *array,int which,cJSON *newitem);
extern void cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem);/* Duplicate a cJSON item */
extern cJSON *cJSON_Duplicate(cJSON *item,int recurse);
/* Duplicate will create a new, identical cJSON item to the one you pass, in new memory that will
need to be released. With recurse!=0, it will duplicate any children connected to the item.
The item->next and ->prev pointers are always zero on return from Duplicate. *//* ParseWithOpts allows you to require (and check) that the JSON is null terminated, and to retrieve the pointer to the final byte parsed. */
extern cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated);extern void cJSON_Minify(char *json);/* Macros for creating things quickly. */
#define cJSON_AddNullToObject(object,name)		cJSON_AddItemToObject(object, name, cJSON_CreateNull())
#define cJSON_AddTrueToObject(object,name)		cJSON_AddItemToObject(object, name, cJSON_CreateTrue())
#define cJSON_AddFalseToObject(object,name)		cJSON_AddItemToObject(object, name, cJSON_CreateFalse())
#define cJSON_AddBoolToObject(object,name,b)	cJSON_AddItemToObject(object, name, cJSON_CreateBool(b))
#define cJSON_AddNumberToObject(object,name,n)	cJSON_AddItemToObject(object, name, cJSON_CreateNumber(n))
#define cJSON_AddStringToObject(object,name,s)	cJSON_AddItemToObject(object, name, cJSON_CreateString(s))/* When assigning an integer value, it needs to be propagated to valuedouble too. */
#define cJSON_SetIntValue(object,val)			((object)?(object)->valueint=(object)->valuedouble=(val):(val))
#define cJSON_SetNumberValue(object,val)		((object)?(object)->valueint=(object)->valuedouble=(val):(val))/* Macro for iterating over an array */
#define cJSON_ArrayForEach(pos, head)			for(pos = (head)->child; pos != NULL; pos = pos->next)#ifdef __cplusplus
}
#endif#endif

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>
#include "mqtt.h"
#include "parse_config.h"
#include "cJSON.h"#define CTRL_PUB_TOPIC "LinuxToWin_lj"
#define SUB_TOPIC "WinToLinux"extern char data[1024]; // 保存接收到的数据
extern int flags;		  // 标志用于判断有没有新数据到达// 发布消息的线程函数
void *mqtt_publish1(void *arg)
{// 发布消息char msg[128] = {0};int i = 0;while (1){sleep(1);sprintf(msg, "{\"test\":%d}", i++);mqtt_publish(CTRL_PUB_TOPIC, msg);//发布消息}return NULL;
}
int main(int argc, char *argv[])
{// mqtt初始化if (0 != mqtt_init()){puts("init_mqtt err");return -1;}// 订阅虚拟仿真发布的数据if (mqtt_subscribe(SUB_TOPIC) < 0){printf("sub err");return -1;}//开启一个消息发布线程pthread_t tid;pthread_create(&tid, NULL, mqtt_publish1, NULL);while (1){if (flags == 1){flags = 0;// 对订阅到的数据进行解析/*温度数据格式：{"tem":浮点数据}湿度数据格式：{"hum":浮点数据}光照数据格式：{"lamp":浮点数据}测试格式  {"test":整型数据}*/cJSON *root = NULL;cJSON *item = NULL; // cjson对象// 对data数据进行分析root = cJSON_Parse(data);if (!root){printf("parse err\n");return -1;}// 根据分析的结果获取我们想要的数据item = cJSON_GetObjectItem(root, "test");if (NULL != item) // 代表是光照传感器{printf("test:%d\n", item->valueint);}}}return 0;
}

Makefile

CC=gcc
#CC=arm-none-linux-gnueabi-gcc
AFLAGS= -c -g -m32
LDFLAGS= -lpthread -m32 -lpaho-mqtt3c -lrt -lm
OBJS=main.o  mqtt.o parse_config.o cJSON.o smart_home:$(OBJS)$(CC) -o $@ $^ $(LDFLAGS)$(OBJS):%.o:%.c$(CC) $(AFLAGS) $< -o $@.PHONY:clean lib
clean:rm *.o smart_homelib:ar crs libmylib.a 
#gcc main.c -o server -L.. -lmylib -lpthread

mqtt.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "MQTTClient.h"
#include <pthread.h>
#include "mqtt.h"
#include "parse_config.h"
#include "cJSON.h"#define QOS 1
#define CLIENTID_PUB "LinuxToWin_lj"MQTTClient client;volatile MQTTClient_deliveryToken deliveredtoken;
char data[1024] = {0};//保存接收到的数据
int flags=0;//标志用于判断有没有新数据到达void delivered(void *context, MQTTClient_deliveryToken dt)
{//printf("Message with token value %d delivery confirmed\n", dt);deliveredtoken = dt;
}int msgarrvd(void *context, char *topicName, int topicLen, MQTTClient_message *message)
{//订阅到的数据保存到数组data中memset(data,0,sizeof(data));//清空数据memcpy(data,message->payload,message->payloadlen);//拷贝数据到data中flags = 1;//设置标志位,表示新的订阅数据到达MQTTClient_freeMessage(&message);//释放消息MQTTClient_free(topicName);//释放topicNamereturn 1;
}void connlost(void *context, char *cause)
{printf("\nConnection lost\n");printf(" cause: %s\n", cause);
}int mqtt_publish(const char *topic, char *msg)
{MQTTClient_message pubmsg = MQTTClient_message_initializer;MQTTClient_deliveryToken token;pubmsg.payload = msg;pubmsg.payloadlen = (int)strlen(msg);pubmsg.qos = QOS;pubmsg.retained = 0;return MQTTClient_publishMessage(client, topic, &pubmsg, &token);
}void exit_mqtt()
{int rc;if ((rc = MQTTClient_disconnect(client, 10000)) != MQTTCLIENT_SUCCESS)printf("Failed to disconnect, return code %d\n", rc);MQTTClient_destroy(&client);
}
int mqtt_subscribe(const char *topic)
{return MQTTClient_subscribe(client, topic, QOS);
}int mqtt_init()
{//解析conf文件中服务器的IP和端口号char uri[128] = {0};GetProfileString(DEF_CONF_FILE,"mqtt","uri",uri);	//设置MQTT连接的参数MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer;int rc;//MQTTClient_create(&client, ADDRESS, CLIENTID_PUB, MQTTCLIENT_PERSISTENCE_NONE, NULL);//创建一个用于连接服务器的MQTTClient对象MQTTClient_create(&client, uri, CLIENTID_PUB, MQTTCLIENT_PERSISTENCE_NONE, NULL);conn_opts.keepAliveInterval = 20;conn_opts.cleansession = 1;//设置MQTT相关回调函数//connlost当连接丢失时会被自动调用//msgarrvd当接收到消息时会被自动调用//delivered当消息被成功发布时会被自动调用MQTTClient_setCallbacks(client, NULL, connlost, msgarrvd, delivered);//连接MQTT服务器if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS){printf("Failed to connect, return code %d\n", rc);return -1;}printf("mqtt connect success\n");return 0;
}

mqtt.h

#ifndef __MQTT_SMART_H_
#define __MQTT_SMART_H_int mqtt_init();
void exit_mqtt();
int mqtt_subscribe(const char*topic);
int mqtt_publish(const char *topic, char *msg);#endif

parse_config.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <ctype.h>#define KEYVALLEN 100/*   删除左边的空格   */
char *l_trim(char *szOutput, const char *szInput)
{assert(szInput != NULL);assert(szOutput != NULL);assert(szOutput != szInput);for (NULL; *szInput != '\0' && isspace(*szInput); ++szInput){;}return strcpy(szOutput, szInput);
}/*   删除右边的空格   */
char *r_trim(char *szOutput, const char *szInput)
{char *p = NULL;assert(szInput != NULL);assert(szOutput != NULL);assert(szOutput != szInput);strcpy(szOutput, szInput);for (p = szOutput + strlen(szOutput) - 1; p >= szOutput && isspace(*p); --p){;}*(++p) = '\0';return szOutput;
}/*   删除两边的空格   */
char *a_trim(char *szOutput, const char *szInput)
{char *p = NULL;assert(szInput != NULL);assert(szOutput != NULL);l_trim(szOutput, szInput);for (p = szOutput + strlen(szOutput) - 1; p >= szOutput && isspace(*p); --p){;}*(++p) = '\0';return szOutput;
}int GetProfileString(char *profile, char *AppName, char *KeyName, char *KeyVal)
{char appname[32], keyname[32];char *buf, *c;char buf_i[KEYVALLEN], buf_o[KEYVALLEN];FILE *fp;int found = 0; /* 1 AppName 2 KeyName */if ((fp = fopen(profile, "r")) == NULL){printf("openfile [%s] error [%s]\n", profile, strerror(errno));return (-1);}fseek(fp, 0, SEEK_SET);memset(appname, 0, sizeof(appname));sprintf(appname, "[%s]", AppName);while (!feof(fp) && fgets(buf_i, KEYVALLEN, fp) != NULL){l_trim(buf_o, buf_i);if (strlen(buf_o) <= 0)continue;buf = NULL;buf = buf_o;if (found == 0){if (buf[0] != '['){continue;}else if (strncmp(buf, appname, strlen(appname)) == 0){found = 1;continue;}}else if (found == 1){if (buf[0] == '#'){continue;}else if (buf[0] == '['){break;}else{if ((c = (char *)strchr(buf, '=')) == NULL)continue;memset(keyname, 0, sizeof(keyname));sscanf(buf, "%[^=|^ |^\t]", keyname);if (strcmp(keyname, KeyName) == 0){sscanf(++c, "%[^\n]", KeyVal);char *KeyVal_o = (char *)malloc(strlen(KeyVal) + 1);if (KeyVal_o != NULL){memset(KeyVal_o, 0, sizeof(KeyVal_o));a_trim(KeyVal_o, KeyVal);if (KeyVal_o && strlen(KeyVal_o) > 0)strcpy(KeyVal, KeyVal_o);free(KeyVal_o);KeyVal_o = NULL;}found = 2;break;}else{continue;}}}}fclose(fp);if (found == 2)return (0);elsereturn (-1);
}

parse_config.h

#ifndef __PARSE_CONFIG_H_
#define __PARSE_CONFIG_H_#define DEF_CONF_FILE   "./smartHome.conf"int GetProfileString(char *profile, char *AppName, char *KeyName, char *KeyVal );#endif

smartHome.conf

[mqtt]
uri=tcp://broker.emqx.io:1883[server]
port=8888

3.QT5中MQTT的配置以及使用

3.1概述

        Qt官方虽然在2017年就已经提供了对MQTT的封装，但是并没有正式加入到Qt的标准库里面，所以需要自己下载源码进行编译。

3.2MQTT源码的下载

Qt官方在github上提供了源代码，地址：https://github.com/qt/qtmqtt

3.3github查找

PS:由于github服务器在国外，咱们访问速度比较慢，所以老师这里直接给大家提供了MQTT源码

3.4MQTT源码的编译

1.编译的前置准备

编译这个源码需要安装perl，否则会报错：perl 不是内部或外部命令，也不是可运行的程序。

这里按照默认安装即可注意，安装完Perl后会自动写入环境变量

perl下载地址：https://www.perl.org/get.html
官网下载速度比较慢，我上传到网盘了，可以在这里下载：
链接：https://pan.baidu.com/s/1p5YOo-FU-ZLJUtuZSN0Rjg 提取码：i0dm

2 编译

直接打开工程文件准备编译

注意：源码路径不能带中文，也不可以有特殊字符

3.编译有可能出现的错误如下：

解决方法：

找到使用的编译器路径，在路径下创建一个文件夹QtMqtt：

将mqtt源码中的h文件都拷贝到这个新创建的文件夹中：

重新编译即可

4.配置QT使用MQTT

这里使用的方式是直接将QtMqtt的库直接部署到Qt安装目录中，这样只需要部署一次，以后在任何工程中引用都不需要再额外导入库了

首先，将源码编译生成目录下的lib中以下3个文件拷贝，并粘贴到Qt安装目录下编译目录下的lib文件夹中去：

4.本地安装mqtt本地服务器

5.QT6中MQTT的配置以及使用

5.1下载源码

1.在GitHub下载对应qt版本的源码

git clone git://code.qt.io/qt/qtmqtt.git -b 6.5.3

这里以6.5.3版本的为例。
这里使用的是VScode的终端，使用cmd也可以。

5.2CMake 编译 Qt MQTT 模块

1.使用QT软件打开CMakeLists.txt。

编译成功文件夹里会生成一个build的文件夹，里面包含Desktop_Qt_6_5_3_MinGW_64_bit-Release这个文件。

5.3.添加QT MQTT模块

这里将编译好的文件放到Qt的安装目录中。
1.移动bin文件里的Qt6Mqtt.dll。注意两者的路径

2.移动include里的QtMqtt文件夹。注意两者的路径

3.移动lib文件夹

注意路径。Qt6Mqtt文件夹

Qt6Mqtt.pc文件

libQt6Mqtt.a Qt6Mqtt.prl文件。

4.移动mkspecs文件

5.modules文件夹

6.复制替换头文件的内容

7.至此mqtt环境已经全部配置完成了。下面我们可以进行验证一下

5.4验证测试

进入到例示程序里面选中该文件。

点击运行，如果之前配置没有出错的话，这里可以出现运行界面。

连接EMQ 免费提供的公共 MQTT Broker，基于 EMQX Platform 构建。服务器访问详情如下：
代理：broker.emqx.io
TCP 端口：1883
SSL/TLS 端口：8883
WebSocket 端口：8083
SSL/TLS 端口：8883
安全 WebSocket 端口：8084
 

6.MQTT的使用

1.添加相关头文件

#include "mainwindow.h"
#include "ui_mainwindow.h"#include <QtCore/QDateTime>
#include <QtMqtt/QMqttClient>
#include <QtWidgets/QMessageBox>

2.窗口

MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow)
{ui->setupUi(this);  //MQTT客户端设置m_client = new QMqttClient(this);
//从界面上获取MQTT服务器的主机名和端口号m_client->setHostname(ui->lineEditHost->text());  m_client->setPort(static_cast<quint16>(ui->spinBoxPort->value()));//信号槽连接
//状态变化处理 调用updateLogStateChange更新当前的状态connect(m_client, &QMqttClient::stateChanged, this, &MainWindow::updateLogStateChange);
//断开连接处理  当断开时调用brokerDisconnected     connect(m_client, &QMqttClient::disconnected, this, &MainWindow::brokerDisconnected);//消息接收处理 当接收到MQTT消息时，记录时间戳，主题和消息内容到日志connect(m_client, &QMqttClient::messageReceived, this, [this](const QByteArray &message, const QMqttTopicName &topic) {const QString content = QDateTime::currentDateTime().toString()+ QLatin1String(" Received Topic: ")+ topic.name()+ QLatin1String(" Message: ")+ message+ QLatin1Char('\n');ui->editLog->insertPlainText(content);});
//Ping相应处理    connect(m_client, &QMqttClient::pingResponseReceived, this, [this]() {const QString content = QDateTime::currentDateTime().toString()+ QLatin1String(" PingResponse")+ QLatin1Char('\n');ui->editLog->insertPlainText(content);});
//动态更新设置   // 主机名文本框内容变化时，自动更新客户端设置connect(ui->lineEditHost, &QLineEdit::textChanged, m_client, &QMqttClient::setHostname);//端口号变化时，通过setClientPort函数更新客户端设置connect(ui->spinBoxPort, QOverload<int>::of(&QSpinBox::valueChanged), this, &MainWindow::setClientPort);//初始化日志状态   updateLogStateChange();
}

3.进行连接

void MainWindow::on_buttonConnect_clicked()
{if (m_client->state() == QMqttClient::Disconnected) {ui->lineEditHost->setEnabled(false);ui->spinBoxPort->setEnabled(false);ui->buttonConnect->setText(tr("Disconnect")); //改变界面显示m_client->connectToHost();  //发起连接请求} else {ui->lineEditHost->setEnabled(true);ui->spinBoxPort->setEnabled(true);ui->buttonConnect->setText(tr("Connect"));m_client->disconnectFromHost(); //断开连接}
}

4.初始化日志状态

void MainWindow::updateLogStateChange()
{const QString content = QDateTime::currentDateTime().toString()+ QLatin1String(": State Change")+ QString::number(m_client->state())+ QLatin1Char('\n');ui->editLog->insertPlainText(content);
}

5.断开连接

void MainWindow::brokerDisconnected()
{ui->lineEditHost->setEnabled(true);ui->spinBoxPort->setEnabled(true);ui->buttonConnect->setText(tr("Connect"));
}

6.端口设置函数

void MainWindow::setClientPort(int p)
{m_client->setPort(static_cast<quint16>(p));
}

7.消息发布函数
从界面获取主题和消息内容
调用 MQTT 客户端发布消息
错误处理：发布失败时显示错误对话框

void MainWindow::on_buttonPublish_clicked()
{if (m_client->publish(ui->lineEditTopic->text(), ui->lineEditMessage->text().toUtf8()) == -1)QMessageBox::critical(this, QLatin1String("Error"), QLatin1String("Could not publish message"));
}

8.主题订阅函数
从界面获取订阅主题
调用 MQTT 客户端订阅主题
错误处理：订阅失败时显示错误对话框

void MainWindow::on_buttonSubscribe_clicked()
{auto subscription = m_client->subscribe(ui->lineEditTopic->text());if (!subscription) {QMessageBox::critical(this, QLatin1String("Error"), QLatin1String("Could not subscribe. Is there a valid connection?"));return;}
}