server.cpp

在linux2.6内核下编的基于socket的通信程序

#include <iostream>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <errno.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
#include <pthread.h>
#include <fstream.h>

using namespace std;

const int MAXSIZE = 4096;  //缓冲区大小
const int MAXLINE = 1000; //在一条消息输出的最大字符数 
const int LISTENQ = 20; //最大监听队列
const int PORT = 5000; //服务器端口号
const int MAXFD = 20; //最大客户连接数
const char *SERVER_IP = "127.0.0.1"; //服务器端ip
char *desfile = "../newfile.c";   //目的文件
const char *dest_file;

void *get_client(void *);
int recvfile(int, char *);
void read_file(const char *, int, int);

int i,maxi = -1;
int client[MAXFD];
int autosockfd = 0;

int main() 
{
	int connfd,listenfd,sockfd;
	socklen_t length;
	struct sockaddr_in server;
	struct sockaddr tcpaddr;
	pthread_t tid;
	listenfd = socket(AF_INET, SOCK_STREAM, 0);
	if(listenfd < 0) 
	{
		cout<<"建立套接口错误"<<endl;
		exit(1);	
	}
	memset(&server, 0, sizeof(server));
	server.sin_family = AF_INET;
	server.sin_port = htons(PORT);
//	server.sin_addr.s_addr = htonl(INADDR_ANY);
	server.sin_addr.s_addr = inet_addr(SERVER_IP);
	if(bind(listenfd, (struct sockaddr*)&server,sizeof(server)) < 0) 
	{
		cout<<"绑定端口失败"<<endl;
		exit(1);
	}
	length = sizeof(server);
	if(getsockname(listenfd, (struct sockaddr*)&server, &length) < 0) 
	{
		cout<<"取服务器端口号失败"<<endl;
		exit(1);
	}
	for(i=0; i<MAXFD; i++) 
	{
		client[i] = -1;
	}
	listen(listenfd, LISTENQ);
	cout<<"服务器监听端口"<<ntohs(server.sin_port)<<endl;
	while(true) 
	{
		autosockfd = connfd = accept(listenfd, &tcpaddr, &length);
	/*	for(i = 0; i < MAXFD; i++) {
			if(client[i] < 0) {
				client[i] = connfd;
				break;
			}*/
			if(i == MAXFD - 1) 
			{
				cout<<"服务器达到最大用户数"<<endl;
				exit(1);			
			}
			if(i > maxi) 
			{
				maxi = i;
			}
			pthread_create(&tid, NULL, &get_client, (void *)connfd);
	//	}
	}
	return 0;
}

void *get_client(void *sockfd) 
{
//	char buf[MAXLINE];
//	char sizebuf[100];
	int rev;
//	int revinfo_size;
	if((int)sockfd < 0) 
	{
		cout<<"新的客户端连接失败。。。。。"<<endl;
	} 
	else 
	{
		cout<<"有新的客户端连接。。。。。。"<<endl;
/*		do 
		{
			memset(buf, 0, sizeof(buf));
			revinfo_size = recv(autosockfd, sizebuf, 1024, 0);
			if(revinfo_size < 0)
			{
				cout<<"读取客户端信息大小失败"<<endl;
			}
			cout<<sizebuf<<endl;
			rev = recv(autosockfd, buf, 1024, 0);*/
			rev = recvfile(autosockfd,desfile);
		//	rev=recv((int)sockfd, buf, 1024, 0);	
			if(rev < 0) 
			{
				cout<<"读取客户机信息失败"<<endl;		
			}
			if(rev == 0) 
			{
				cout<<"客户机已终止连接"<<endl;
			} 
	/*		else 
			{
			        cout<<recvbuf<<endl;
				for(i = 0; i <= maxi; i++) 
				{
					send(client[i], buf, strlen(buf)+1, 0 );
					send(autosockfd, buf, strlen(buf)+1,0);					
				}
			} 
		} while (rev != 0); */
		 	
	}
	cout<<"客户机发送过来的信息如下："<<endl;
	read_file(desfile, ios::in, 0);
	close((int)sockfd);
	return NULL;
}

/* 从客户端接收文件 */ 
int recvfile(int cli, char *desfile) 
{ 
	int buflen = 0; //接收缓冲区数组的长度
	int len = 0;  //接收缓冲区数组实际长度
	int num = 0; //从客户端接收数据的大小
	int flag;  //所有数据接收完成的标志
	FILE *desfp; 	//目的文件指针			
	char buf[MAXSIZE];   //写目的文件的数据
	char recvbuf[MAXSIZE];  //从客户端接收数据的存储数组
	char *p;    //指向recvbuf数组的指针
	int i;    //int的长度
	if((desfp = fopen(desfile, "wb")) == NULL) 
	{ 
		perror("open exefile error"); 
		exit(1); 
	} 
	buf[0] = '\0'; 
	recvbuf[0] = '\0'; 
	i = sizeof(buflen); 
	if((num=recv(cli, recvbuf, sizeof(recvbuf), 0)) == -1) 
	{ 
		perror("recv data error"); 
		exit(1); 
	} 
	printf("\nnum:%d\t", num); 
	p = recvbuf; 
	memcpy(&buflen, p, i); 
	printf("buflen:%d\t", buflen); 
	if(buflen != 0) 
	{ 
		flag = 1; 
		p = p + i; 
		num = num - i; 
	} 
	while(flag) 
	{ 
		while(buflen <= num) 
		{ 
			len = buflen; 
			memcpy(buf, p, len); 
			if(fwrite(buf, 1, len, desfp) != len)  //写文件
			{ 
				perror("fwrite error"); 
				exit(1); 
			} 
			num = num - len;  //改变指针偏移量 
			buflen = buflen - len; 
			if(num > 0) 
			{ 
				p = p + len; 
				memcpy(&buflen, p, i); 
				printf("buflen:%d\t", buflen); 
				p = p + i; 
				num = num - i; 
				if(buflen == 0) 
				{ 
					flag = 0; 
					break; 
				} 
			} 
			else 
			{ 
				break; 
			} 
		} 
		if(flag == 0) 
		{ 
			break; 
		} 
		if(buflen > num) 
		{ 
			if(num > 0) 
			{ 
				len = num; 
				memcpy(buf, p, len); 
				if(fwrite(buf, 1, len,desfp) != len) 
				{ 
					perror("fwrite error"); 
					exit(1); 
				} 
				buflen = buflen - len; 
			}	 
		} 
		if((num = recv(cli, recvbuf, sizeof(recvbuf), 0)) == -1) 
		{ 
			perror("recv data error"); 
			exit(1); 
		}
		cout<<recvbuf<<endl; 
		printf("\nnum:%d\t", num); 
		p = recvbuf;
		if(buflen == 0) 
		{ 
			memcpy(&buflen, p, i); 
			printf("buflen:%d\t", buflen); 
			p = p + i; 
			num = num - i; 
			if(buflen == 0) 
			{ 
				flag=0; 
			} 
		} 
	} 
	buf[0] = '\0'; 
	strcpy(buf, "copy done!"); 
	if(send(cli, buf, strlen(buf), 0)==-1) 
	{ 
		perror("send data error"); 
		exit(1); 
	} 
	printf("\nbuf:%s\n", buf);
	printf("\nrecvbuf:%s\n", recvbuf); 
	fclose(desfp); 
//	cout<<recvbuf<<endl;
	cout<<endl;
	return 1; 
}

void read_file(const char *desfile, int in,int access)
{
	fstream src;
	src.open(desfile);
	char c;
	while(!src.eof())
	{
		c = src.get();
		cout<<c;
	}
	src.close();
}