server_thread.c

用Unix下的socket实现的并发服务器

/*该服务器采用的实现方法是多线程，在这里面有一个主线程，用它来临
听是否有连接，每当有连接是它就会生成一个子线程来处理客户端的请求，
处理完后子线程退出*/
#include<string.h>
#include<stdlib.h>
#include<stdio.h>
#include<strings.h>
#include<unistd.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<pthread.h>

#define PORT 1234
#define BACKLOG 5
#define MAXDATASIZE 1000

void process_cli(int connectfd, sockaddr_in client);
void *start_routine(void *arg);

typedef struct ARG { 
int connfd;
sockaddr_in client;
};

main()
{
int listenfd, connectfd;
pthread_t thread;
ARG *arg;
struct sockaddr_in server;
struct sockaddr_in client;
socklen_t sin_size;

if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)//创建套接字
{
perror("Creating socket failed.");
exit(1);
}

int opt = SO_REUSEADDR;
setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));//设置地址可重用

bzero(&server, sizeof(server));
server.sin_family = AF_INET;
server.sin_port = htons(PORT);
server.sin_addr.s_addr = htonl(INADDR_ANY);

if (bind(listenfd, (struct sockaddr *)&server, sizeof(struct sockaddr)) == -1)//绑定
{
perror("Bind fail.");
exit(1);
}


if (listen(listenfd, BACKLOG) == -1)//监听
{
perror("listen fail");
exit(1);
}

sin_size = sizeof(struct sockaddr_in);


while (1)
{
	if ((connectfd = accept(listenfd, (struct sockaddr *)&client, &sin_size)) == -1){ //连接
		if (error == EINTR)
			continue;
perror("accept fail.");
exit(1);
}

arg =(ARG *)malloc(sizeof(ARG));//此时为处理子线程分配一个结构，采用动态分配是为了避免之间的干扰
arg->connfd = connectfd;
memcpy((void *)&arg->client, &client, sizeof(client));

if (pthread_create(&thread, NULL, start_routine, (void *)arg))//每有连接到来就创建一个线程来处理它
{
perror("Pthread_creart fail.");
exit(1);
}
}
close(listenfd);
}

void process_cli(int connectfd, sockaddr_in clien)
{
int num;
char recvbuf[MAXDATASIZE];
char sendbuf[MAXDATASIZE];
char cli_name[MAXDATASIZE];

printf("You got a connection from %s.", inet_ntoa(clien.sin_addr));

num = recv(connectfd, cli_name, MAXDATASIZE, 0);


if (num == 0)
{
close(connectfd);
printf("Client disconnected.\n");
return;
}

cli_name[num - 1] = '\0';
printf("Client's name is %s.\n", cli_name);

while (num = recv(connectfd, recvbuf, MAXDATASIZE, 0))
{
	if (error = EINTR)
		continue;
recvbuf[num] = '\0';
printf("Received client(%s) message:%s", cli_name , recvbuf);
int i;
for (i=0; i<num-1; i++)
{
sendbuf[i] = recvbuf[num - i - 2];
}

sendbuf[num - 1] = '\0';
send(connectfd, sendbuf, strlen(sendbuf), 0);
}
close(connectfd);
}

void *start_routine(void *arg)
{
ARG *info;
info = (ARG *)arg;

process_cli(info->connfd, info->client);
free(arg);
pthread_exit(NULL);//子线程处理完后退出来
}