https://www.eclipse.org/paho/downloads.php
eclipse/paho.mqtt.c库(使用v1.3.0)的下载地址是:https://github.com/eclipse/paho.mqtt.c/tree/v1.3.0
1、paho.mqtt.c-1.3.0\CMakeLists.txt,使能PAHO_BUILD_STATIC 和PAHO_BUILD_SAMPLES
## build options
SET(PAHO_WITH_SSL FALSE CACHE BOOL "Flag that defines whether to build ssl-enabled binaries too. ")
SET(PAHO_BUILD_STATIC TRUE CACHE BOOL "Build static library") #firecat modify
SET(PAHO_BUILD_DOCUMENTATION FALSE CACHE BOOL "Create and install the HTML based API documentation (requires Doxygen)")
SET(PAHO_BUILD_SAMPLES TRUE CACHE BOOL "Build sample programs") #firecat modify
SET(PAHO_BUILD_DEB_PACKAGE FALSE CACHE BOOL "Build debian package")
SET(PAHO_ENABLE_TESTING TRUE CACHE BOOL "Build tests and run")
SET(PAHO_ENABLE_CPACK TRUE CACHE BOOL "Enable CPack")
2、paho.mqtt.c-1.3.0\src\samples\CMakeLists.txt
#*******************************************************************************
# Copyright (c) 2015, 2017 logi.cals GmbH and others
#
# 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:
# Rainer Poisel - initial version
# Ian Craggs - update sample names
#*******************************************************************************/
# Note: on OS X you should install XCode and the associated command-line tools
## compilation/linkage settings
INCLUDE_DIRECTORIES(
.
${CMAKE_SOURCE_DIR}/src
${CMAKE_BINARY_DIR}
)
IF (WIN32)
ADD_DEFINITIONS(/DCMAKE_BUILD /D_CRT_SECURE_NO_DEPRECATE)
ENDIF()
# sample files c
#ADD_EXECUTABLE(paho_c_pub paho_c_pub.c pubsub_opts.c) #firecat
#ADD_EXECUTABLE(paho_c_sub paho_c_sub.c pubsub_opts.c)
#ADD_EXECUTABLE(paho_cs_pub paho_cs_pub.c pubsub_opts.c)
#ADD_EXECUTABLE(paho_cs_sub paho_cs_sub.c pubsub_opts.c)
#TARGET_LINK_LIBRARIES(paho_c_pub paho-mqtt3as)
#TARGET_LINK_LIBRARIES(paho_c_sub paho-mqtt3as)
#TARGET_LINK_LIBRARIES(paho_cs_pub paho-mqtt3cs)
#TARGET_LINK_LIBRARIES(paho_cs_sub paho-mqtt3cs)
ADD_EXECUTABLE(MQTTAsync_subscribe MQTTAsync_subscribe.c)
ADD_EXECUTABLE(MQTTAsync_publish MQTTAsync_publish.c)
ADD_EXECUTABLE(MQTTClient_subscribe MQTTClient_subscribe.c)
ADD_EXECUTABLE(MQTTClient_publish MQTTClient_publish.c)
ADD_EXECUTABLE(MQTTClient_publish_async MQTTClient_publish_async.c)
TARGET_LINK_LIBRARIES(MQTTAsync_subscribe paho-mqtt3a)
TARGET_LINK_LIBRARIES(MQTTAsync_publish paho-mqtt3a)
TARGET_LINK_LIBRARIES(MQTTClient_subscribe paho-mqtt3c)
TARGET_LINK_LIBRARIES(MQTTClient_publish paho-mqtt3c)
TARGET_LINK_LIBRARIES(MQTTClient_publish_async paho-mqtt3c)
#INSTALL(TARGETS paho_c_sub #firecat
# paho_c_pub
# paho_cs_sub
# paho_cs_pub
# MQTTAsync_subscribe
# MQTTAsync_publish
# MQTTClient_subscribe
# MQTTClient_publish
# MQTTClient_publish_async
# RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
# LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})
3、使用cmake release编译,生成以下的动态库和静态库文件:
The Paho C client comprises four shared libraries:
libmqttv3a.so - asynchronous
libmqttv3as.so - asynchronous with SSL
libmqttv3c.so - "classic" / synchronous
libmqttv3cs.so - "classic" / synchronous with SSL
Optionally, using the CMake build, you can build static versions of those libraries.
libpaho-mqtt3a.so
libpaho-mqtt3a.so.1
libpaho-mqtt3a.so.1.3.0
libpaho-mqtt3a-static.a
libpaho-mqtt3c.so
libpaho-mqtt3c.so.1
libpaho-mqtt3c.so.1.3.0
libpaho-mqtt3c-static.a
把它们一起拷贝到路径:/usr/local/lib/
此时需要在/etc/ld.so.conf中加入库文件所在的目录:/usr/local/lib/
然后在终端执行命令,使之生效:
[root@localhost etc]# ldconfig
注意,/usr/local/lib/每次有库文件更新,都需要终端重新运行一次ldconfig这条命令。
4、使用案例
/*******************************************************************************
* Copyright (c) 2012, 2017 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 contribution
*******************************************************************************/
#include
#include
#include
#include "MQTTClient.h"
#include
#include
#include
#include /*setrlimit */
#include //daemonize
#define ADDRESS "tcp://192.168.83.128:1883"
#define CLIENTID "id001"
#define TOPIC "keepalived"
#define PAYLOAD "Hello World!"
#define QOS 0
#define USERNAME "inTerm"
#define PASSWORD "in2018"
static int run = 1;
volatile MQTTClient_deliveryToken deliveredtoken;
void daemonize(void) { //come from /redis/server.c/daemonize()
int fd;
if (fork() != 0) exit(0); /* parent exits */
setsid(); /* create a new session */
/* Every output goes to /dev/null. If Redis is daemonized but
* the 'logfile' is set to 'stdout' in the configuration file
* it will not log at all. */
if ((fd = open("/dev/null", O_RDWR, 0)) != -1) {
dup2(fd, STDIN_FILENO);
dup2(fd, STDOUT_FILENO);
dup2(fd, STDERR_FILENO);
if (fd > STDERR_FILENO) close(fd);
}
}
void signal_exit_func(int signo)
{
run = 0;
printf("exit signo is %d\n", signo);
}
void signal_exit_handler()
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = signal_exit_func;
sigaction(SIGINT, &sa, NULL);//当按下ctrl+c时,它的效果就是发送SIGINT信号
sigaction(SIGTERM, &sa, NULL);//kill pid
sigaction(SIGQUIT, &sa, NULL);//ctrl+\代表退出SIGQUIT
//SIGSTOP和SIGKILL信号是不可捕获的,所以下面两句话写了等于没有写
sigaction(SIGKILL, &sa, NULL);//kill -9 pid
sigaction(SIGSTOP, &sa, NULL);//ctrl+z代表停止
//#define SIGTERM 15
//#define SIGKILL 9
//kill和kill -9,两个命令在linux中都有杀死进程的效果,然而两命令的执行过程却大有不同,在程序中如果用错了,可能会造成莫名其妙的现象。
//执行kill pid命令,系统会发送一个SIGTERM信号给对应的程序。
//执行kill -9 pid命令,系统给对应程序发送的信号是SIGKILL,即exit。exit信号不会被系统阻塞,所以kill -9能顺利杀掉进程。
}
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)
{
int i;
char* payloadptr;
printf("Message arrived\n");
printf(" topic: %s\n", topicName);
printf(" message: ");
payloadptr = message->payload;
for(i=0; ipayloadlen; i++)
{
putchar(*payloadptr++);
}
putchar('\n');
MQTTClient_freeMessage(&message);
MQTTClient_free(topicName);
return 1;
}
void connlost(void *context, char *cause)//心跳时间达到,如果没有收到服务器的reponse,客户端的socket会自动关闭
{
printf("\nConnection lost\n");
printf(" cause: %s\n", cause);
exit(EXIT_FAILURE); //firecat
}
//./MQTTClient_firecat "tcp://192.168.83.128:1883" "id001"
int main(int argc, char* argv[])
{
int background = 1;//firecat add
if (background)
{
daemonize();
}
//signal(SIGHUP, SIG_IGN); //开启的话,就捕获不到终端窗口关闭的信号了。即窗口关闭,进程仍然进行。
signal(SIGPIPE, SIG_IGN);
char *serverURI;
char *clientId;
if (argc == 1)
{
serverURI = ADDRESS;
clientId = CLIENTID;
}
else if (argc == 3)
{
serverURI = argv[1];
clientId = argv[2];
}
else
{
printf("argc error\n");
exit(EXIT_FAILURE);
}
MQTTClient client;
MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer;
int rc;
int ch;
MQTTClient_create(&client, serverURI, clientId,
MQTTCLIENT_PERSISTENCE_NONE, NULL);
conn_opts.keepAliveInterval = 60;
conn_opts.cleansession = 1;
conn_opts.MQTTVersion = MQTTVERSION_3_1_1;
conn_opts.username = USERNAME;
conn_opts.password = PASSWORD;
MQTTClient_setCallbacks(client, NULL, connlost, msgarrvd, delivered);
if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS)
{
printf("Failed to connect, return code %d\n", rc);
exit(EXIT_FAILURE);
}
printf("Subscribing to topic %s\nfor client %s using QoS%d\n\n"
"Press Q to quit\n\n", TOPIC, CLIENTID, QOS);
MQTTClient_subscribe(client, TOPIC, QOS);
if (background)
{
while (run)
{
sleep(1);
}
}
else
{
do
{
ch = getchar();
} while(ch!='Q' && ch != 'q');
}
MQTTClient_unsubscribe(client, TOPIC);
MQTTClient_disconnect(client, 10000);
MQTTClient_destroy(&client);
return rc;
}