一、单对单通信测试
应用函数 socket、bind、connect、listen、accept、recv、send(win下的函数)等
1、客户端demo client.cpp
#include<WINSOCK2.H>
#include<STDIO.H>
#include<iostream>
#include<cstring>
using namespace std;
#pragma comment(lib, "ws2_32.lib")
#define CONNECT_COUNT_MAX 20
#define CONNECT_INTERVAL_MS 1000
int main()
{
WORD sockVersion = MAKEWORD(2, 2);
WSADATA data;
if(WSAStartup(sockVersion, &data)!=0)
{
return 0;
}
while(true){
SOCKET sclient = socket(AF_INET, SOCK_STREAM, 0);//IPPROTO_TCP
if(sclient == INVALID_SOCKET)
{
printf("invalid socket!");
WSACleanup();
system("pause");
return 0;
}
// 设定客户端协议族、端口、ip信息
sockaddr_in clientAddr;
clientAddr.sin_family = AF_INET;
clientAddr.sin_port = htons(8888);
clientAddr.sin_addr.S_un.S_addr = inet_addr("127.6.6.2");
if (bind(sclient,(struct sockaddr *)&clientAddr,sizeof(clientAddr))==0){ //client信息绑定到clientfd上
printf("client socket bind success\n");
};
// 设定服务端协议族、端口、ip信息
sockaddr_in serAddr;
serAddr.sin_family = AF_INET;
serAddr.sin_port = htons(9999);
serAddr.sin_addr.S_un.S_addr = inet_addr("127.6.6.254");
// while(true){
int connect_flag_ = 0; //TCP connect 结果标志位
int connect_count_ = 0; //TCP connect 重试次数
while(connect_count_ < CONNECT_COUNT_MAX){
connect_flag_ = connect(sclient, (sockaddr *)&serAddr, sizeof(serAddr));
if(connect_flag_ == SOCKET_ERROR){ //连接失败
printf("connect error, retry time: [%d]!\n", connect_count_);
connect_count_ ++;
Sleep(CONNECT_INTERVAL_MS); //休眠一段时间再重试connect
}else{
printf("connect success, retry time: [%d]!\n", connect_count_);
break;
}
}
if(connect_count_ == CONNECT_COUNT_MAX){ //达到了最大connect次数,结束
printf("connect error ,retry finshed!\n");
closesocket(sclient);
WSACleanup();
system("pause");
return 0;
}
string client_id = "[client_1] : ";
bool input_flag_ = false; //选择传入手动输入消息还是默认消息
// string data;
const char * sendData;
int client_send_flag_ = 0;
if(input_flag_){
char data[128] = {};
cin >> data;
sendData = (client_id + data).c_str(); //string转const char*
cout << "client msg : " << sendData << endl;
client_send_flag_ = send(sclient, sendData, strlen(sendData), 0);
}else{
char *sendData = "我是北方的狼";
cout << "client msg : " << sendData << endl;
client_send_flag_ = send(sclient, sendData, strlen(sendData), 0);
Sleep(3000);
};
//send()用来将数据由指定的socket传给对方主机
/*
int send(int s, const void * msg, int len, unsigned int flags)
s为已建立好连接的socket,msg指向数据内容,len则为数据长度,参数flags一般设0
成功则返回实际传送出去的字符数,失败返回-1,错误原因存于error
*/
if(client_send_flag_ >= 0){ //send 失败或成功提示
printf(" send msg success!\n");
}else{
printf(" send msg fail!!\n");
}
char recData[255];
int ret = recv(sclient, recData, 255, 0);
/* 函数原型:int recv( SOCKET s, char *buf, int len, int flags)
功能: 用recv函数从TCP连接的另一端接收数据。
参数一:指定接收端套接字描述符;
参数二:指明一个缓冲区,该缓冲区用来存放recv函数接收到的数据;
参数三:指明buf的长度;
参数四 :一般置为0。
返回值 : 读出来的字节大小
*/
if(ret>0){
recData[ret] = 0x00;
printf(recData);
}
closesocket(sclient);
}
// }
WSACleanup();
return 0;
}
特点
1、轮询重试
2、测试时可先于服务端启动
3、发送消息可以选择周期发或者手动输入;(bug:目前手动输入过长字符会有发送异常的情况出现)
2、服务端demo server.cpp
#include <stdio.h>
#include <winsock2.h>
#include<iostream>
#include<cstring>
#include<Windows.h>
#include<future>
// #include<promise>
#pragma comment(lib,"ws2_32.lib")
#define DATA_SIZE 1024
using namespace std;
#if 0
future_status getRecvResult(SOCKET sClientfd, char *revData , int* ret){
std::future<int> ret1 = std::async(std::launch::async, recv , sClientfd, revData, DATA_SIZE, 0); //异步调用
std::future_status sts = ret1.wait_for(std::chrono::seconds(1)); //设置超时时间 s'
*ret = ret1.get();
return sts;
}
#endif
int main(int argc, char* argv[])
{
//初始化WSA
WORD sockVersion = MAKEWORD(2,2);
WSADATA wsaData;
if(WSAStartup(sockVersion, &wsaData)!=0)
{
return 0;
}
//创建套接字
SOCKET slisten = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(slisten == INVALID_SOCKET)
{
printf("socket error !");
return 0;
}
//绑定IP和端口
sockaddr_in serveraddr;
serveraddr.sin_family = AF_INET;
serveraddr.sin_port = htons(9999);
// serveraddr.sin_addr.S_un.S_addr = INADDR_ANY; //可以是系统端口
serveraddr.sin_addr.S_un.S_addr = inet_addr("127.6.6.254");
if(bind(slisten, (LPSOCKADDR)&serveraddr, sizeof(serveraddr)) == SOCKET_ERROR)
{
printf("bind error !");
}
//开始监听
if(listen(slisten, 5) == SOCKET_ERROR)
{
printf("listen error !");
return 0;
}
//循环接收数据
SOCKET sClientfd;
sockaddr_in remoteAddr;
int nAddrlen = sizeof(remoteAddr);
while (true)
{
printf("等待连接...\n");
sClientfd = accept(slisten, (SOCKADDR *)&remoteAddr, &nAddrlen);
/*
listen监听客户端来的链接,accept将客户端的信息绑定到一个socket上,也就是给客户端创建一个socket,通过返回值返回给我们客户端的socket。
accept函数的第一个参数为服务器的socket描述字,第二个参数为指向struct sockaddr *的指针,用于返回客户端的协议地址,第三个参数为协议地址的长度。
如果accpet成功,那么其返回值是由内核自动生成的一个全新的描述字,代表与返回客户的TCP连接。
成功:
返回值就是给客户端包好的socket; 与客户端通信就靠这个
失败:
返回INVALIE_SOCKET; 通过WSAGetLastError()得到错误码
*/
// while (true)
// {
if(sClientfd <= 0 )
{
printf("accept error !");
cout << WSAGetLastError() << endl;
Sleep(2000);
continue;
}
printf("接受到一个连接:%s \r\n", inet_ntoa(remoteAddr.sin_addr));
//接收数据
// char revData[2] = {};
// int data_size = sizeof(revData);
string tmp = "";
int ret = 0;
do //怕数据太长,一次recv copy不完,为了把client端一次发的的消息拼接、打印
{
char revData[DATA_SIZE] = {};
revData[DATA_SIZE] = 0x00; // 抵消数组后面的字符
cout << "start " << revData <<endl;
/* // 下面的异步超时操作是为了把client端一次发的的消息拼接、打印(主要是一条消息最后一次数据大小 = DATA_SIZE的情况);;不过有bug,没想好怎么解决
std::future<int> ret1 = std::async(std::launch::async, recv , sClientfd, revData, DATA_SIZE, 0); //异步调用
std::future_status sts = ret1.wait_for(std::chrono::seconds(1)); //设置超时时间 s'
if(sts == std::future_status::ready){
// ret = ret1.get();
printf("超时时间内收到了回复\n");
}else if(sts == std::future_status::timeout){
printf("设定时间内无消息\n");
ret = 0;
break;
}
*/
ret = recv(sClientfd, revData, DATA_SIZE, 0); // 在主线程操作,如果recv大小正好是个整数包,一直阻塞在这,不会给该client返回消息;
//这是上面do while想做的事情可能带来的影响
cout << "server ret = " << ret << endl;
if(ret <= 0){
printf("receive msg error\n");
// system("pause");
Sleep(3000);
break;
}
if(ret < DATA_SIZE){
revData[ret] = 0x00;
cout << "last phase " << revData <<endl;
}
tmp = tmp + revData;
cout << "tmp :[" << tmp << "] , leave"<<endl;
} while (ret == DATA_SIZE);
cout <<'['<< tmp << ']'<<endl;
//发送数据
const char * sendData = "你好,TCP客户端!\n";
send(sClientfd, sendData, strlen(sendData), 0);
closesocket(sClientfd);
Sleep(1000);
}
closesocket(slisten);
WSACleanup();
return 0;
}
特点
1、为了一次打印client发送的消息,做了一点愚蠢的特殊处理。。。
2、没有做超时,socket没有消息会一直阻塞;
3、验证
编译:
g++ server.cpp -o server -lwsock32
g++ client.cpp -o client -lwsock32
二、多个客户端通信测试(有bug)
新增加select的使用
1、客户端新增demo client_2.cpp
#include<WINSOCK2.H>
#include<STDIO.H>
#include<iostream>
#include<cstring>
using namespace std;
#pragma comment(lib, "ws2_32.lib")
#define CONNECT_COUNT_MAX 20
#define CONNECT_INTERVAL_MS 1000
#define INPUT_FLAG true
int main()
{
WORD sockVersion = MAKEWORD(2, 2);
WSADATA data;
if(WSAStartup(sockVersion, &data)!=0)
{
return 0;
}
while(true){
SOCKET sclient = socket(AF_INET, SOCK_STREAM, 0);//IPPROTO_TCP
if(sclient == INVALID_SOCKET)
{
printf("invalid socket!");
WSACleanup();
system("pause");
return 0;
}
// 设定客户端协议族、端口、ip信息
sockaddr_in clientAddr;
clientAddr.sin_family = AF_INET;
clientAddr.sin_port = htons(8888);
clientAddr.sin_addr.S_un.S_addr = inet_addr("127.6.6.4");
if (bind(sclient,(struct sockaddr *)&clientAddr,sizeof(clientAddr))==0){ //client信息绑定到clientfd上
printf("client socket bind success\n");
};
// 设定服务端协议族、端口、ip信息
sockaddr_in serAddr;
serAddr.sin_family = AF_INET;
serAddr.sin_port = htons(9999);
serAddr.sin_addr.S_un.S_addr = inet_addr("127.6.6.254");
// while(true){
int connect_flag_ = 0; //TCP connect 结果标志位
int connect_count_ = 0; //TCP connect 重试次数
while(connect_count_ < CONNECT_COUNT_MAX){
connect_flag_ = connect(sclient, (sockaddr *)&serAddr, sizeof(serAddr));
if(connect_flag_ == SOCKET_ERROR){ //连接失败
printf("connect error, retry time: [%d]!\n", connect_count_);
connect_count_ ++;
Sleep(CONNECT_INTERVAL_MS); //休眠一段时间再重试connect
}else{
printf("connect success, retry time: [%d]!\n", connect_count_);
break;
}
}
if(connect_count_ == CONNECT_COUNT_MAX){ //达到了最大connect次数,结束
printf("connect error ,retry finshed!\n");
closesocket(sclient);
WSACleanup();
system("pause");
return 0;
}
string client_id = "[client_1] : ";
bool input_flag_ = INPUT_FLAG; //选择传入手动输入消息还是默认消息
// string data;
const char * sendData;
int client_send_flag_ = 0;
if(input_flag_){
char data[128] = {};
cin >> data;
sendData = (client_id + data).c_str(); //string转const char*
cout << "client msg : " << sendData << endl;
client_send_flag_ = send(sclient, sendData, strlen(sendData), 0);
}else{
char *sendData = "我是北方的羊";
cout << "client msg : " << sendData << endl;
client_send_flag_ = send(sclient, sendData, strlen(sendData), 0);
Sleep(3000);
};
//send()用来将数据由指定的socket传给对方主机
/*
int send(int s, const void * msg, int len, unsigned int flags)
s为已建立好连接的socket,msg指向数据内容,len则为数据长度,参数flags一般设0
成功则返回实际传送出去的字符数,失败返回-1,错误原因存于error
*/
if(client_send_flag_ >= 0){ //send 失败或成功提示
printf(" send msg success!\n");
}else{
printf(" send msg fail!!\n");
}
char recData[255];
int ret = recv(sclient, recData, 255, 0);
/* 函数原型:int recv( SOCKET s, char *buf, int len, int flags)
功能: 用recv函数从TCP连接的另一端接收数据。
参数一:指定接收端套接字描述符;
参数二:指明一个缓冲区,该缓冲区用来存放recv函数接收到的数据;
参数三:指明buf的长度;
参数四 :一般置为0。
返回值 : 读出来的字节大小
*/
if(ret>0){
recData[ret] = 0x00;
printf(recData);
}
closesocket(sclient);
}
// }
WSACleanup();
return 0;
}
2、服务端demo server_select.cpp
#include <stdio.h>
#include <winsock2.h>
#include<iostream>
#include<cstring>
#include<Windows.h>
#include<future>
// #include<promise>
#pragma comment(lib,"ws2_32.lib")
#define DATA_SIZE 1024
using namespace std;
#if 0
future_status getRecvResult(SOCKET sClientfd, char *revData , int* ret){
std::future<int> ret1 = std::async(std::launch::async, recv , sClientfd, revData, DATA_SIZE, 0); //异步调用
std::future_status sts = ret1.wait_for(std::chrono::seconds(1)); //设置超时时间 s'
*ret = ret1.get();
return sts;
}
#endif
int main(int argc, char* argv[])
{
//初始化WSA
WORD sockVersion = MAKEWORD(2,2);
WSADATA wsaData;
if(WSAStartup(sockVersion, &wsaData)!=0)
{
return 0;
}
//创建套接字
SOCKET slisten = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(slisten == INVALID_SOCKET)
{
printf("socket error !");
return 0;
}
//绑定IP和端口
sockaddr_in serveraddr;
serveraddr.sin_family = AF_INET;
serveraddr.sin_port = htons(9999);
// serveraddr.sin_addr.S_un.S_addr = INADDR_ANY; //可以是系统端口
serveraddr.sin_addr.S_un.S_addr = inet_addr("127.6.6.254");
if(bind(slisten, (LPSOCKADDR)&serveraddr, sizeof(serveraddr)) == SOCKET_ERROR)
{
printf("bind error !");
}
//开始监听
if(listen(slisten, 5) == SOCKET_ERROR)
{
printf("listen error !");
return 0;
}
//循环接收数据
SOCKET sClientfd;
sockaddr_in remoteAddr;
int nAddrlen = sizeof(remoteAddr);
// select 相关设置
fd_set rfds, readset, wfds, writeset;
SOCKET Clientfd[1024];
int maxfd = slisten;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_SET(slisten, &rfds);
while (true)
{
printf("等待连接...\n");
int selectRet = select(maxfd+1,&rfds,NULL,NULL,NULL);//select()调用返回处于就绪状态并且已经包含在fd_set结构中的描述字总数;如果超时则返回0;
//否则的话,返回SOCKET_ERROR错误,应用程序可通过WSAGetLastError获取相应错误代码。
if(selectRet <= 0){
printf("select error [%d]\n", selectRet); // >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Sleep(3000);
// continue;
}
cout << "selectRet = " << selectRet << endl;
cout << "maxfd = " << maxfd << endl;
cout << "slisten = " << slisten << endl;
for (int fd = 0; fd <= maxfd; fd++){
if(FD_ISSET(fd,&rfds)){
if(fd == slisten){
sClientfd = accept(slisten, (SOCKADDR *)&remoteAddr, &nAddrlen); //如果监听的socket有消息,就接受client的socket
FD_SET(sClientfd, &rfds);
maxfd = sClientfd > maxfd ? sClientfd : maxfd; // 更新maxfd
break;
}else{
break;
}
}
else{
// cout << "fd = " << fd << endl;
}
}
// if(FD_ISSET(slisten,&rfds)){
// sClientfd = accept(slisten, (SOCKADDR *)&remoteAddr, &nAddrlen);
// }
/*
listen监听客户端来的链接,accept将客户端的信息绑定到一个socket上,也就是给客户端创建一个socket,通过返回值返回给我们客户端的socket。
accept函数的第一个参数为服务器的socket描述字,第二个参数为指向struct sockaddr *的指针,用于返回客户端的协议地址,第三个参数为协议地址的长度。
如果accpet成功,那么其返回值是由内核自动生成的一个全新的描述字,代表与返回客户的TCP连接。
成功:
返回值就是给客户端包好的socket; 与客户端通信就靠这个
失败:
返回INVALIE_SOCKET; 通过WSAGetLastError()得到错误码
*/
// while (true)
// {
if(sClientfd <= 0 )
{
printf("accept error !");
cout << WSAGetLastError() << endl;
Sleep(2000);
continue;
}
printf("接受到一个连接:%s \r\n", inet_ntoa(remoteAddr.sin_addr));
//接收数据
// char revData[2] = {};
// int data_size = sizeof(revData);
string tmp = "";
int ret = 0;
do //怕数据太长,一次recv copy不完,为了把client端一次发的的消息拼接、打印
{
char revData[DATA_SIZE] = {};
revData[DATA_SIZE] = 0x00; // 抵消数组后面的字符
cout << "start " << revData <<endl;
/* // 下面的异步超时操作是为了把client端一次发的的消息拼接、打印(主要是一条消息最后一次数据大小 = DATA_SIZE的情况);;不过有bug,没想好怎么解决
std::future<int> ret1 = std::async(std::launch::async, recv , sClientfd, revData, DATA_SIZE, 0); //异步调用
std::future_status sts = ret1.wait_for(std::chrono::seconds(1)); //设置超时时间 s'
if(sts == std::future_status::ready){
// ret = ret1.get();
printf("超时时间内收到了回复\n");
}else if(sts == std::future_status::timeout){
printf("设定时间内无消息\n");
ret = 0;
break;
}
*/
ret = recv(sClientfd, revData, DATA_SIZE, 0); // 在主线程操作,如果recv大小正好是个整数包,一直阻塞在这,不会给该client返回消息;
//这是上面do while想做的事情可能带来的影响
cout << "server ret = " << ret << endl;
if(ret <= 0){
printf("receive msg error\n");
// system("pause");
Sleep(3000);
break;
}
if(ret < DATA_SIZE){
revData[ret] = 0x00;
cout << "last phase " << revData <<endl;
}
tmp = tmp + revData;
cout << "tmp :[" << tmp << "] , leave"<<endl;
} while (ret == DATA_SIZE);
cout <<'['<< tmp << ']'<<endl;
//发送数据
const char * sendData = "你好,TCP客户端!\n";
send(sClientfd, sendData, strlen(sendData), 0);
closesocket(sClientfd);
Sleep(1000);
}
closesocket(slisten);
WSACleanup();
return 0;
}
特点
目前也没超时,不能很好的处理多个客户端的互相影响
3、验证
编译执行,用到上面所有的client
手动输入的client会把服务端的进程阻塞住,导致另一个client的消息也进不来,手动输入消息后,会暂时解除当前阻塞,问题不小,小白太难了,后面再搞