LWIP配置
服务器端实现
客户端实现
错误分析
一。LWIP配置(FREERTOS配置,ETH配置,LWIP配置)
1.FREERTOS配置
为什么要修改定时源为Tim1?不用systick?
原因:HAL库与FREERTOS都需要使用systick,两者冲突,所以修改时钟源,让FREERTOS使用Tim1。
2.ETH配置
3.LWIP配置
不使用DHCP
4.步骤:
(1)freertos.c中会自己出现一个Lwip初始化
运行后结果:命令行中输入ping 192.168.1.10有回复
二。服务器端
实验一:《stm32作为服务器端,COMMBOX串口作为客户端》
1.功能分析
小写转大写
2.步骤:
(1)建立socket_tcp_server.h
#ifndef SOCKET_TCP_SERVER_H
#define SOCKET_TCP_SERVER_H#define SERVER_IP "192.168.1.11"
#define SERVER_PORT 6666
#define BUFF_SIZE 1024void vTcpServerTask(void);#endif
(2)建立socket_tcp_server.c,并添加到文件中
#include "socket_tcp_server.h"
#include "lwip/sockets.h"
#include "ctype.h"char ReadBuff[BUFF_SIZE];/*** @brief TCP 服务器任务* @param None* @retval None*/
void vTcpServerTask(void){int sfd, cfd, n, i;struct sockaddr_in server_addr, client_addr;socklen_t client_addr_len;//创建socketsfd = socket(AF_INET, SOCK_STREAM, 0);server_addr.sin_family = AF_INET;server_addr.sin_port = htons(SERVER_PORT);server_addr.sin_addr.s_addr = htonl(INADDR_ANY);//绑定socketbind(sfd, (struct sockaddr *)&server_addr, sizeof(server_addr));//监听socketlisten(sfd, 5);//等待客户端连接client_addr_len = sizeof(client_addr);cfd = accept(sfd, (struct sockaddr *)&client_addr, &client_addr_len);printf("client is connect cfd = %d\r\n",cfd);while(1){//等待客户端发送数据n = read(cfd, ReadBuff, BUFF_SIZE);//进行大小写转换for(i = 0; i < n; i++){ReadBuff[i] = toupper(ReadBuff[i]); }//写回客户端write(cfd, ReadBuff, n);}
}
(3)freertos.c中网络任务中,添加服务器运行函数。
不要忘记添加头文件
vTcpServerTask();
3.现象演示
(1)使用COMMBOX串口调试工程,添加socket网络客户端 ,目标ip为stm32的ip.端口在.h中
(2)stm32客户端发送的字母变大写
三。客户端创建
实验二:《stm32作为客户端,COMMBOX串口作为服务器端》
1.创建socket_tcp_client.c与socket_tcp_client.h
(1)socket_tcp_client.c
#include "socket_tcp_server.h"
#include "socket_tcp_client.h"
#include "lwip/sockets.h"
#include "ctype.h"static char ReadBuff[BUFF_SIZE];void vTcpClientTask(void)
{int cfd, n, i;struct sockaddr_in server_addr;//创建socketcfd = socket(AF_INET, SOCK_STREAM, 0);server_addr.sin_family = AF_INET;server_addr.sin_port = htons(SERVER_PORT);server_addr.sin_addr.s_addr = inet_addr(SERVER_IP);//连接到服务器connect(cfd, (struct sockaddr*)&server_addr, sizeof(server_addr));printf("server is connect ok\r\n");while(1){//等待服务器发送数据n = read(cfd, ReadBuff, BUFF_SIZE);//进行大小写转换for(i = 0; i < n; i++){ReadBuff[i] = toupper(ReadBuff[i]); }//写回服务器write(cfd, ReadBuff, n);}
}
(2)socket_tcp_client.h
#ifndef _SOCKET_TCP_CLIENT_H
#define _SOCKET_TCP_CLIENT_Hvoid vTcpClientTask(void);#endif
可能遇到的问题:
由于打开了防火墙,所以无法连接
补充:上述代码的问题
1.代码封装性不好
2.代码对边界错误提示太少
四。代码的优化
1.函数在封装,文件为socket_warp.c与socket_warp.h
(1)socket_warp.h
#ifndef _SOCKET_WRAP_H
#define _SOCKET_WRAP_H#include "lwip/sockets.h"int Socket(int domain, int type, int protocol);int Bind(int sockfd, const struct sockaddr *addr, socklen_t addrlen);int Listen(int sockfd, int backlog);int Accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen);
int Connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen);int Write(int fd,const void *buf,size_t nbytes);
int Read(int fd,void *buf,size_t nbyte);int Sendto(int sockfd, const void *msg, int len, unsigned int flags, const struct sockaddr *to, int tolen);
int Recvfrom(int sockfd, void *buf, int len, unsigned int flags, struct sockaddr *from, socklen_t *fromlen);#endif
(2)socket_warp.c
#include "socket_wrap.h"
#include "FreeRTOS.h"
#include "task.h"int Socket(int domain, int type, int protocol){int fd;fd=socket(domain,type,protocol);if(fd<0){printf("create socket error\n");//没有创建完成,那么这个任务也没有必要运行,直接切换上下文//返回一个小于零的数vTaskDelete(NULL);}return fd;
}int Bind(int sockfd, const struct sockaddr *addr, socklen_t addrlen){int ret;ret=bind(sockfd,addr,addrlen);if(ret < 0){printf("bind socket error\r\n");//当调用删除任务,就会切换上下文,CPU执行其他任务vTaskDelete(NULL); }return ret;
}int Listen(int sockfd, int backlog){int ret;ret=listen(sockfd,backlog);if(ret<0){printf("listen socket error\n");vTaskDelete(NULL);}return ret;
}int Accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen){int fd;
again: fd=accept(sockfd,addr,addrlen);if(fd<0){printf("accept socket error\n");goto again;}return fd;
}
int Connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen){int ret;ret=connect(sockfd,addr,addrlen);if(ret<0){printf("connect socket error\n");//先关闭当前的socket,其实内部是删除这个socket的内存块,不删除会导致下次无法生成close(sockfd);}return ret;
}int Write(int fd,const void *buf,size_t nbytes){int ret;ret=write(fd,buf,nbytes);//没有书写完成就关闭socketif(ret<0){printf("write socket error\n");close(fd);}return ret;
}
int Read(int fd,void *buf,size_t nbyte){int ret;ret=read(fd,buf,nbyte);if(ret==0){printf("read socket is close\n");close(fd);}else if(ret<0){printf("read socket error\n");close(fd);}
}int Sendto(int sockfd, const void *msg, int len, unsigned int flags, const struct sockaddr *to, int tolen){int ret;
again: ret=sendto(sockfd,msg,len,flags,to,tolen);if(ret<0){printf("sendto socket error\n");goto again;}return ret;
}int Recvfrom(int sockfd, void *buf, int len, unsigned int flags, struct sockaddr *from, socklen_t *fromlen){int ret;
again: ret=recvfrom(sockfd,buf,len,flags,from,fromlen);if(ret<0){printf("recvfrom socket error\n");goto again; }return ret;
}
上述为封装函数,包括tcp_server,tcp_client已经后续的udp_server
2.socket_tcp_server.c与socket_tcp_client.c
1.socket_tcp_server.c
#include "socket_udp_server.h"
#include "socket_tcp_server.h"
#include "socket_wrap.h"
#include "ctype.h"static char ReadBuff[BUFF_SIZE];void vUdpServerTask(){int sfd, n, i;struct sockaddr_in server_addr, client_addr;socklen_t client_addr_len;int optval=1;//创建socketsfd=Socket(AF_INET, SOCK_DGRAM, 0);setsockopt(sfd,SOL_SOCKET ,SO_BROADCAST,&optval,sizeof(optval));//绑定socketserver_addr.sin_family = AF_INET;server_addr.sin_port = htons(SERVER_PORT);server_addr.sin_addr.s_addr = htonl(INADDR_ANY);Bind(sfd, (struct sockaddr *)&server_addr, sizeof(server_addr));//处理client_addr_len=sizeof(client_addr);while(1){//等待客户端发送数据n = Recvfrom(sfd, ReadBuff, BUFF_SIZE, 0, (struct sockaddr *)&client_addr, &client_addr_len);ReadBuff[n] = '\0';printf("recv data:%s\r\n",ReadBuff);//进行大小写转换for(i = 0; i < n; i++){ ReadBuff[i] = toupper(ReadBuff[i]); }//写回客户端Sendto(sfd, ReadBuff, n, 0, (struct sockaddr *)&client_addr, client_addr_len);}}
2.socket_tcp_client.c
#include "socket_tcp_server.h"
#include "socket_tcp_client.h"
#include "socket_wrap.h"
#include "ctype.h"
#include "FreeRTOS.h"
#include "task.h"#include "string.h"static char ReadBuff[BUFF_SIZE];void vTcpClientTask(void)
{int cfd, n, i, ret;struct sockaddr_in server_addr;// int so_reuseaddr_val = 1;
again://创建socketcfd = Socket(AF_UNSPEC, SOCK_STREAM, 0);//使能socket层 心跳检测
// setsockopt(cfd, SOL_SOCKET, SO_REUSEADDR, &so_reuseaddr_val, sizeof(int));server_addr.sin_family = AF_INET;server_addr.sin_port = htons(SERVER_PORT);server_addr.sin_addr.s_addr = inet_addr(SERVER_IP); //连接到服务器//connect 其实是一个阻塞接口,内部要完成TCP的三次握手,当然有超时机制,所以我们需要等一段时间,才能重新连接到服务器ret = connect(cfd, (struct sockaddr*)&server_addr, sizeof(server_addr));if(ret < 0){//100ms去连接一次服务器vTaskDelay(1000);printf("connect fail\r\n");goto again;}printf("server is connect ok\r\n");while(1){//等待服务器发送数据n = Read(cfd, ReadBuff, BUFF_SIZE);if(n <= 0){goto again;}//进行大小写转换for(i = 0; i < n; i++){ReadBuff[i] = toupper(ReadBuff[i]); }//写回服务器n = Write(cfd, ReadBuff, n);if(n <= 0){goto again;}}
}
结果:pc端的COMMBOX创建或者关闭服务器或者客户端时,串口都会打印出内容,提示打开或者关闭。