前言
我们在这里做2件事情：
1）编译 paho.mqtt、mosquitto 2个开源项目的c版本库（mosquitto库没有用上）
2）编译好 依赖 paho.mqtt的库编写例程 + mosquitto 服务器。
host平台 ：Ubuntu 16.04
arm 平台 ： s5p6818
ssl ： openssl-1.0.2t
MQTT-client : paho.mqtt.c
现在我们就来进行MQTT客户端的移植。
MQTT服务器(Broker)在很多 云服务器中自带了，没有特殊需求是不做移植的；而且就算做了 Broker 移植，也相对简单。
主机准备
使用以下脚本即可。
之前《搭建MQTT通信环境，并抓包测试》 没有介绍在：Linux下 编译运行 mosquitto 服务器，所以在下面的脚本中也有介绍，具体参考：
make_mosquitto ()
##
# Copyright By Schips, All Rights Reserved
# https://gitee.com/schips/
# File Name: make.sh
# Created : Sat 30 Nov 2019 01:56:37 PM CST
##
#!/bin/sh
BUILD_HOST=arm-linux-
ARM_GCC=${BUILD_HOST}gcc
ARM_CPP=${BUILD_HOST}g++
BASE=`pwd`
OUTPUT_PATH=${BASE}/install
OPENSSL=openssl-1.0.2t
make_dirs () {
#为了方便管理，创建有关的目录
cd ${BASE} && mkdir compressed install source -p
}
tget () { #try wget
filename=`basename $1`
echo "Downloading [${filename}]..."
if [ ! -f ${filename} ];then
wget $1
fi
echo "[OK] Downloaded [${filename}] "
}
tgit () { #try git and tar
filename=`basename $1 | sed 's/.git//g'`
echo "Clone [${filename}]..."
if [ ! -f ${filename}.tgz ];then
git clone $1
rm ${filename}/.git* -rf
echo "Making a tar file."
tar -zcf ${filename}.tgz ${filename}
rm ${filename} -rf
fi
echo "[OK] Cloned [${filename}] "
}
download_package () {
cd ${BASE}/compressed
#下载包
tget https://www.openssl.org/source/${OPENSSL}.tar.gz
tgit https://github.com/eclipse/paho.mqtt.c.git
tgit https://github.com/eclipse/mosquitto.git
}
tar_package () {
cd ${BASE}/compressed
ls * > /tmp/list.txt
for TAR in `cat /tmp/list.txt`
do
tar -xf $TAR -C ../source
done
rm -rf /tmp/list.txt
}
pre_make_ssl () {
cd ${BASE}/source/${OPENSSL}
startLine=`sed -n '/install_html_docs:/=' Makefile`
echo $startLine
# 为了避免 多行结果
for startline in $startLine
do
lineAfter=99
endLine=`expr $startline + 999`
sed -i $startline','$endLine'd' Makefile
echo "install_html_docs:" >> Makefile
echo " @echo skip by Schips" >> Makefile
echo "install_docs:" >> Makefile
echo " @echo skip by Schips" >> Makefile
echo "# DO NOT DELETE THIS LINE -- make depend depends on it." >> Makefile
break
done
}
make_ssl () {
# 编译安装 zlib
cd ${BASE}/source/${OPENSSL}
rm ${OUTPUT_PATH}/${OPENSSL} -rf
echo "SSL ABOUT"
CC=${ARM_GCC} ./Configure no-asm shared --prefix=${OUTPUT_PATH}/${OPENSSL}
sed 's/-m64//g' -i Makefile # 删除-m64 关键字 (arm-gcc 不支持)
#sudo mv /usr/bin/pod2man /usr/bin/pod2man_bak
#mv doc/apps /tmp/
pre_make_ssl
make && make install
}
make_paho_mqtt_c () {
cd ${BASE}/source/paho.mqtt.c
make CFLAGS+="-I ${OUTPUT_PATH}/${OPENSSL}/include"
LDFLAGS+="-L${OUTPUT_PATH}/${OPENSSL}/lib"
CC=${ARM_GCC}
prefix=${OUTPUT_PATH}/paho.mqtt.c
# BUG: make install 不符合我们的意愿
rm ${OUTPUT_PATH}/paho.mqtt.c -rf
mkdir ${OUTPUT_PATH}/paho.mqtt.c/lib -p
mkdir ${OUTPUT_PATH}/paho.mqtt.c/bin -p
mkdir ${OUTPUT_PATH}/paho.mqtt.c/include -p
cp ${BASE}/source/paho.mqtt.c/build/output/lib* ${OUTPUT_PATH}/paho.mqtt.c/lib -d -v
cp ${BASE}/source/paho.mqtt.c/build/output/samples ${OUTPUT_PATH}/paho.mqtt.c/bin -r -v
cp ${BASE}/source/paho.mqtt.c/build/output/test ${OUTPUT_PATH}/paho.mqtt.c/bin -r -v
cp ${BASE}/source/paho.mqtt.c/src/*.h ${OUTPUT_PATH}/paho.mqtt.c/include -v
}
make_mosquitto () {
cd ${BASE}/source/mosquitto
sed -r -i "/WITH_DOCS:=/ s/.*/WITH_DOCS:=no/" config.mk
sed -r -i "/WITH_SRV:=/ s/.*/WITH_SRV:=no/" config.mk
sed -r -i "/WITH_UUID:=/ s/.*/WITH_UUID:=no/" config.mk
sed -r -i "/WITH_WEBSOCKETS:=/ s/.*/WITH_WEBSOCKETS:=no/" config.mk
sed -r -i "/WITH_STRIP:=/ s/.*/WITH_STRIP:=yes/" config.mk
# 不添加 ssl 支持
sed -r -i "/WITH_TLS:=/ s/.*/WITH_TLS:=no/" config.mk
sed -r -i "/WITH_TLS_PSK:=/ s/.*/WITH_TLS_PSK:=no/" config.mk
# 指定工具链
sed -i "N;2aCC=${BUILD_HOST}gcc" config.mk
sed -i "N;2aCXX=${BUILD_HOST}g++" config.mk
sed -i "N;2aCPP=${BUILD_HOST}g++" config.mk
sed -i "N;2aCC=${BUILD_HOST}gcc" config.mk
sed -i "N;2aAR=${BUILD_HOST}ar" config.mk
sed -i "N;2aLD=${BUILD_HOST}ld" config.mk
sed -r -i "/STRIP?=/ s/.*/STRIP?=${BUILD_HOST}strip/" config.mk
# 设置输出路径
echo "DESTDIR=${OUTPUT_PATH}/mosquitto" >> config.mk
echo "prefix=\" >> config.mk
make && make install
# 添加 ssl 支持 下编译的 mosquitto
#sed -r -i "/WITH_TLS:=/ s/.*/WITH_TLS:=yes/" config.mk
#sed -r -i "/WITH_TLS_PSK:=/ s/.*/WITH_TLS_PSK:=yes/" config.mk
#make
# CFLAGS+="-I ${OUTPUT_PATH}/${OPENSSL}/include"
# LDFLAGS+="-L${OUTPUT_PATH}/${OPENSSL}/lib -lssl -lcrypto"
#make
# CFLAGS+="-I ${OUTPUT_PATH}/${OPENSSL}/include"
# LDFLAGS+="-L${OUTPUT_PATH}/${OPENSSL}/lib -lssl -lcrypto"
# install
}
make_dirs
download_package
tar_package
make_ssl
make_paho_mqtt_c
make_mosquitto
exit $?
目标板准备
将install 下运行库拷贝到板子上，添加到路径即可。
测试
使用以下的测试程序，服务器根据自己的需求进行指定
有关的例程在 ${paho_mqtt_c}/src/samples 可以找到。
/*
# Copyright By Schips, All Rights Reserved
# https://gitee.com/schips/
#
# File Name: main.cpp
# Created : Sun 09 Feb 2020 10:14:44 AM CST
*/
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <MQTTClient.h> /* MQTT头文件的位置 */
#include <sys/time.h>
#include <termios.h>
#define ADDRESS "tcp://localhost:1883" /* 指定服务器的ip地址 这里使用本机的 mosquitto 进行测试使用 */
#define CLIENTID "ExampleClientPub"
#define TOPIC "MQTT Examples"
#define PAYLOAD "Hello World!"
#define QOS 1
#define TIMEOUT 10000L
using namespace std;
int main(int argc, char* argv[])
{
MQTTClient client;
MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer;
MQTTClient_message pubmsg = MQTTClient_message_initializer;
MQTTClient_deliveryToken token;
MQTTClient_message *receivemsg = NULL ;
char* topicName_rev = NULL;
int topicLen_rev;
int rc;
int i;
MQTTClient_create(&client, ADDRESS, CLIENTID,
MQTTCLIENT_PERSISTENCE_NONE, NULL);
conn_opts.keepAliveInterval = 60;
conn_opts.cleansession = 1;
if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS)
{
printf("Failed to connect, return code %d
", rc);
exit(-1);
}
pubmsg.payload = (void *)PAYLOAD;
pubmsg.payloadlen = strlen(PAYLOAD);
pubmsg.qos = QOS;
pubmsg.retained = 0;
MQTTClient_subscribe(client, "test", 1); /* 订阅一个客户端 的一个话题*/
usleep(10000);
MQTTClient_publishMessage(client, TOPIC, &pubmsg, &token); /* 发送消息 */
printf("Waiting for up to %d seconds for publication of %s
"
"on topic %s for client with ClientID: %s
",
(int)(TIMEOUT/1000), PAYLOAD, TOPIC, CLIENTID);
rc = MQTTClient_waitForCompletion(client, token, TIMEOUT);
printf("Message with delivery token %d delivered
", token);
for(;;)
{
if(MQTTClient_isConnected(client) == true) /* 检测连接状态 */
{
printf("alive
");
}else{
printf(" no alive
");
break;
}
rc = MQTTClient_receive(client,&topicName_rev, &topicLen_rev, &receivemsg,5000); /* 接收消息 */
if(rc == MQTTCLIENT_SUCCESS)
{
printf("Message REv %d delivered
", rc);
printf("topicName: %s topicName_LEN: %d
", topicName_rev,topicLen_rev);
if(topicName_rev != NULL) /* 滤掉心跳包 */
{
printf("topicName: ");
for(i=0;i<topicLen_rev;i++)
{
printf(" %c ", topicName_rev[i]);
}
printf("
");
printf("Data: %s len:%d msgid: %d
",(char *)receivemsg->payload,receivemsg->payloadlen,receivemsg->msgid);
if(strcmp((char *)receivemsg->payload,"ESC") == 0)
{
printf("ESC
");
break;
}
}
}
usleep(10000);
usleep(100000);
}
MQTTClient_disconnect(client, 10000);
MQTTClient_destroy(&client);
return rc;
}
编译命令
arm-linux-g++ -I ./paho.mqtt.c/src -L ./paho.mqtt.c/build/output/ -lpaho-mqtt3c main.cpp -o client