20155308&20155316 2017-2018-1 《信息安全系统设计基础》实验三

20155308&20155316 2017-2018-1 《信息安全系统设计基础》实验三

并发程序-1

• 学习使用Linux命令wc(1)

• 基于Linux Socket程序设计实现wc（1）服务器(端口号是你学号的后6位)和客户端

• 客户端传一个文本文件给服务器

• 服务器返加文本文件中的单词数

• 上方提交代码

• 附件提交测试截图，至少要测试附件中的两个文件

首先先学习一下命令wc使用：

• 利用man命令查看wc命令使用

实例为：

1. 统计行数

$wc –l file

1. 统计单词数

$wc –w file

1. 统计字符数

$wc –c file

1. 统计流中的字符数

$echo –n 1234 | wc –c

实验过程

实验代码

Server.c

#include<netinet/in.h>  // sockaddr_in
#include<sys/types.h>   // socket
#include<sys/socket.h>  // socket
#include<stdio.h>       // printf
#include<stdlib.h>      // exit
#include<string.h>      // bzero
#include<unistd.h>
#define SERVER_PORT 155316
#define LENGTH_OF_LISTEN_QUEUE 20
#define BUFFER_SIZE 1024
#define FILE_NAME_MAX_SIZE 512
int CountWordsOfEuropeanTxtFile(char *szFileName);
int CountWordsInOneLine(const char *szLine);
int main(void)
{
    // 声明并初始化一个服务器端的socket地址结构
    struct sockaddr_in server_addr;
    bzero(&server_addr, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = htons(INADDR_ANY);
    server_addr.sin_port = htons(SERVER_PORT);
   // 创建socket，若成功，返回socket描述符
    int server_socket_fd = socket(PF_INET, SOCK_STREAM, 0);
    if(server_socket_fd < 0)
    {
        perror("Create Socket Failed:");
        exit(1);
    }
    int opt = 1;
    setsockopt(server_socket_fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
 // 绑定socket和socket地址结构
    if(-1 == (bind(server_socket_fd, (struct sockaddr*)&server_addr, sizeof(server_addr))))
    {
        perror("Server Bind Failed:");
        exit(1);
    }
     // socket监听
    if(-1 == (listen(server_socket_fd, LENGTH_OF_LISTEN_QUEUE)))
    {
        perror("Server Listen Failed:");
        exit(1);
    }
while(1)
    {
        // 定义客户端的socket地址结构
        struct sockaddr_in client_addr;
        socklen_t client_addr_length = sizeof(client_addr);
 // 接受连接请求，返回一个新的socket(描述符)，这个新socket用于同连接的客户端通信
        // accept函数会把连接到的客户端信息写到client_addr中
        int new_server_socket_fd = accept(server_socket_fd, (struct sockaddr*)&client_addr, &client_addr_length);
        if(new_server_socket_fd < 0)
        {
            perror("Server Accept Failed:");
            break;
        }
        // recv函数接收数据到缓冲区buffer中
        char buffer[BUFFER_SIZE];
        bzero(buffer, BUFFER_SIZE);
        if(recv(new_server_socket_fd, buffer, BUFFER_SIZE, 0) < 0)
        {
            perror("Server Recieve Data Failed:");
            break;
        }
        // 然后从buffer(缓冲区)拷贝到file_name中
        char file_name[FILE_NAME_MAX_SIZE+1];
        bzero(file_name, FILE_NAME_MAX_SIZE+1);
        strncpy(file_name, buffer, strlen(buffer)>FILE_NAME_MAX_SIZE?FILE_NAME_MAX_SIZE:strlen(buffer));
        printf("5316:%s\n", file_name);
	int count=0;
	bzero(buffer, BUFFER_SIZE);
	count = CountWordsOfEuropeanTxtFile(file_name);
	sprintf(buffer,"%d", count);
        if(send(new_server_socket_fd, buffer, sizeof(buffer), 0) < 0)
        {
               printf("Send File:%s Failed./n", file_name);
        }
	bzero(buffer, BUFFER_SIZE);
        /*/ 打开文件并读取文件数据
        FILE *fp = fopen(file_name, "r");
        if(NULL == fp)
        {
            printf("File:%s Not Found\n", file_name);
        }
        else
        {
            bzero(buffer, BUFFER_SIZE);
            int length = 0;
            / 每读取一段数据，便将其发送给客户端，循环直到文件读完为止
            while((length = fread(buffer, sizeof(char), BUFFER_SIZE, fp)) > 0)
            {
                if(send(new_server_socket_fd, buffer, length, 0) < 0)
                {
                    printf("Send File:%s Failed./n", file_name);
                    break;
                }
                bzero(buffer, BUFFER_SIZE);
            }
            / 关闭文件
            fclose(fp);
            printf("File:%s Transfer Successful!\n", file_name);
        }*/
        // 关闭与客户端的连接
        close(new_server_socket_fd);
    }
    // 关闭监听用的socket
    close(server_socket_fd);
    return 0;
}
int CountWordsOfEuropeanTxtFile(char *szFileName)
{
	int nWords = 0;//词计数变量，初始值为0
	FILE *fp; //文件指针
	char carrBuffer[1024];//每行字符缓冲，每行最多1024个字符
	//打开文件
	if ((fp = fopen(szFileName,  "r")) == NULL)
	{
		return -1;	//文件打开不成功是返回-1
	}
	while (!feof(fp))//如果没有读到文件末尾
	{
		//从文件中读一行
		if (fgets(carrBuffer, sizeof(carrBuffer),fp) != NULL)
			//统计每行词数
			nWords += CountWordsInOneLine(carrBuffer);
	}
	//关闭文件
	fclose(fp);
	return nWords;
}
int CountWordsInOneLine(const char *szLine)
{
	int nWords = 0;
	int i=0;
	for (;i<strlen(szLine);i++)
	{
		if (*(szLine+i)!=' ')
		{
			nWords++;
			while ((*(szLine+i)!=' ')&&(*(szLine+i)!='\0'))
			{
				i++;
			}
		}

	}
			//printf("%d\t",nWords);

	return nWords;
}

Client.c

#include<netinet/in.h>   // sockaddr_in
#include<sys/types.h>    // socket
#include<sys/socket.h>   // socket
#include<stdio.h>        // printf
#include<stdlib.h>       // exit
#include<string.h>       // bzero
#include<unistd.h>
#include<stdlib.h>
#define SERVER_PORT 155316
#define BUFFER_SIZE 1024
#define FILE_NAME_MAX_SIZE 512
int main()
{
    // 声明并初始化一个客户端的socket地址结构
    struct sockaddr_in client_addr;
    bzero(&client_addr, sizeof(client_addr));
    client_addr.sin_family = AF_INET;
    client_addr.sin_addr.s_addr = htons(INADDR_ANY);
    client_addr.sin_port = htons(0);
    // 创建socket，若成功，返回socket描述符
    int client_socket_fd = socket(AF_INET, SOCK_STREAM, 0);
    if(client_socket_fd < 0)
    {
        perror("Create Socket Failed:");
        exit(1);
    }
    // 绑定客户端的socket和客户端的socket地址结构 非必需
    if(-1 == (bind(client_socket_fd, (struct sockaddr*)&client_addr, sizeof(client_addr))))
    {
        perror("Client Bind Failed:");
        exit(1);
    }
    // 声明一个服务器端的socket地址结构，并用服务器那边的IP地址及端口对其进行初始化，用于后面的连接
    struct sockaddr_in server_addr;
    bzero(&server_addr, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    if(inet_pton(AF_INET, "127.0.0.1", &server_addr.sin_addr) == 0)
    {
        perror("Server IP Address Error:");
        exit(1);
    }
    server_addr.sin_port = htons(SERVER_PORT);
    socklen_t server_addr_length = sizeof(server_addr);
    // 向服务器发起连接，连接成功后client_socket_fd代表了客户端和服务器的一个socket连接
    if(connect(client_socket_fd, (struct sockaddr*)&server_addr, server_addr_length) < 0)
    {
        perror("Can Not Connect To Server IP:");
        exit(0);
    }
    // 输入文件名 并放到缓冲区buffer中等待发送
    char file_name[FILE_NAME_MAX_SIZE+1];
    bzero(file_name, FILE_NAME_MAX_SIZE+1);
    printf("Please Input File Name On Server:\t");
    scanf("%s", file_name);
    char buffer[BUFFER_SIZE];
    bzero(buffer, BUFFER_SIZE);
    strncpy(buffer, file_name, strlen(file_name)>BUFFER_SIZE?BUFFER_SIZE:strlen(file_name));
    // 向服务器发送buffer中的数据
    if(send(client_socket_fd, buffer, BUFFER_SIZE, 0) < 0)
    {
        perror("Send File Name Failed:");
        exit(1);
    }
    //int count=0;
    int length=0;
    bzero(buffer, BUFFER_SIZE);
    length = recv(client_socket_fd, buffer, BUFFER_SIZE, 0);
    buffer[length] = '\0';
    printf("count=%s\n", buffer);
    bzero(buffer, BUFFER_SIZE);
    /* / 打开文件，准备写入
     / FILE *fp = fopen(file_name, "w");
    if(NULL == fp)
    {
        printf("File:\t%s Can Not Open To Write\n", file_name);
        exit(1);
    }
    / 从服务器接收数据到buffer中
    / 每接收一段数据，便将其写入文件中，循环直到文件接收完并写完为止
    bzero(buffer, BUFFER_SIZE);
    int length = 0;
    while((length = recv(client_socket_fd, buffer, BUFFER_SIZE, 0)) > 0)
    {
        if(fwrite(buffer, sizeof(char), length, fp) < length)
        {
            printf("File:\t%s Write Failed\n", file_name);
            break;
        }
        bzero(buffer, BUFFER_SIZE);
    }
    / 接收成功后，关闭文件，关闭socket
    printf("Receive File:\t%s From Server IP Successful!\n", file_name);
    fclose(fp);
    */
    close(client_socket_fd);
    return 0;
}

实验操作

• 查阅相关资料，了解wc是可以对一个文件内的单词数进行一个统计
• 对程序初步设计分为两块，一块是C/S程序，一块是对传入文件进行单词统计
• 具体程序见CS_tfile

实验问题及解答

出现的问题

• 编译client server程序时出现如下警告（因为当时没有截图，以下截图为实景还原）
• 
• 
• 说是宏定义的常量过大，以及没有inet_pton函数
• 这两个都是警告
• 实际运行时还是可以正常运行，这说明我们可以暂时不管这两个警告
  
  

并发程序-2

• 使用多线程实现wc服务器并使用同步互斥机制保证计数正确
• 上方提交代码
• 下方提交测试
• 对比单线程版本的性能，并分析原因

实验过程

实验代码

thread_server.c

#include<stdlib.h>
#include<pthread.h>
#include<sys/socket.h>
#include<sys/types.h>       //pthread_t , pthread_attr_t and so on.
#include<stdio.h>
#include<netinet/in.h>      //structure sockaddr_in
#include<arpa/inet.h>       //Func : htonl; htons; ntohl; ntohs
#include<assert.h>          //Func :assert
#include<string.h>          //Func :memset bzero
#include<unistd.h>          //Func :close,write,read
#define SOCK_PORT 9988
#define BUFFER_LENGTH 1024
#define MAX_CONN_LIMIT 512     //MAX connection limit
static void Data_handle(void * sock_fd);   //Only can be seen in the file
int CountWordsOfEuropeanTxtFile(char *szFileName);
int CountWordsInOneLine(const char *szLine);
int main()
{
    int sockfd_server;
    int sockfd;
    int fd_temp;
    struct sockaddr_in s_addr_in;
    struct sockaddr_in s_addr_client;
    int client_length;
    sockfd_server = socket(AF_INET,SOCK_STREAM,0);  //ipv4,TCP
    assert(sockfd_server != -1);
    //before bind(), set the attr of structure sockaddr.
    memset(&s_addr_in,0,sizeof(s_addr_in));
    s_addr_in.sin_family = AF_INET;
    s_addr_in.sin_addr.s_addr = htonl(INADDR_ANY);  //trans addr from uint32_t host byte order to network byte order.
    s_addr_in.sin_port = htons(SOCK_PORT);          //trans port from uint16_t host byte order to network byte order.
    fd_temp = bind(sockfd_server,(const struct sockaddr *)(&s_addr_in),sizeof(s_addr_in));
    if(fd_temp == -1)
    {
        fprintf(stderr,"bind error!\n");
        exit(1);
    }
    fd_temp = listen(sockfd_server,MAX_CONN_LIMIT);
    if(fd_temp == -1)
    {
        fprintf(stderr,"listen error!\n");
        exit(1);
    }
    while(1)
    {
        printf("waiting for new connection...\n");
        pthread_t thread_id;
        client_length = sizeof(s_addr_client);
        //Block here. Until server accpets a new connection.
        sockfd = accept(sockfd_server,(struct sockaddr * restrict)(&s_addr_client),(socklen_t *)(&client_length));
        if(sockfd == -1)
        {
            fprintf(stderr,"Accept error!\n");
            continue;                               //ignore current socket ,continue while loop.
        }
        printf("A new connection occurs!\n");
        if(pthread_create(&thread_id,NULL,(void *)(&Data_handle),(void *)(&sockfd)) == -1)
        {
            fprintf(stderr,"pthread_create error!\n");
            break;                                  //break while loop
        }
    }
    //Clear
    int ret = shutdown(sockfd_server,SHUT_WR); //shut down the all or part of a full-duplex connection.
    assert(ret != -1);
    printf("Server shuts down\n");
    return 0;
}
static void Data_handle(void * sock_fd)
{
    int fd = *((int *)sock_fd);
    int i_recvBytes;
    char data_recv[BUFFER_LENGTH];
    const char * data_send = "Server has received your request!\n";
    while(1)
    {
        printf("waiting for file_name...\n");
        //Reset data.
        memset(data_recv,0,BUFFER_LENGTH);
        i_recvBytes = read(fd,data_recv,BUFFER_LENGTH);
        if(i_recvBytes == 0)
        {
            printf("Maybe the client has closed\n");
            break;
        }
        if(i_recvBytes == -1)
        {
            fprintf(stderr,"read error!\n");
            break;
        }
        if(strcmp(data_recv,"quit")==0)
        {
            printf("Quit command!\n");
            break;                           //Break the while loop.
        }
        printf("read from client : %s\n",data_recv);

	char buffer[BUFFER_LENGTH];
	int count=0;
	bzero(buffer, BUFFER_LENGTH);
	count = CountWordsOfEuropeanTxtFile(data_recv);
	sprintf(buffer,"%d", count);
        send(fd, buffer, sizeof(buffer), 0);
        if(write(fd,data_send,strlen(data_send)) == -1)
        {
            break;
        }
    }
    //Clear
    printf("terminating current client_connection...\n");
    close(fd);            //close a file descriptor.
    pthread_exit(NULL);   //terminate calling thread!
}
int CountWordsOfEuropeanTxtFile(char *szFileName)
{
	int nWords = 0;//词计数变量，初始值为0
	FILE *fp; //文件指针
	char carrBuffer[1024];//每行字符缓冲，每行最多1024个字符
	//打开文件
	if ((fp = fopen(szFileName,  "r")) == NULL)
	{
		return -1;	//文件打开不成功是返回-1
	}
	while (!feof(fp))//如果没有读到文件末尾
	{
		//从文件中读一行
		if (fgets(carrBuffer, sizeof(carrBuffer),fp) != NULL)
			//统计每行词数
			nWords += CountWordsInOneLine(carrBuffer);
	}

	//关闭文件
	fclose(fp);
	return nWords;
}
int CountWordsInOneLine(const char *szLine)
{
	int nWords = 0;
	int i=0;
	for (;i<strlen(szLine);i++)
	{
		if (*(szLine+i)!=' ')
		{
			nWords++;
			while ((*(szLine+i)!=' ')&&(*(szLine+i)!='\0'))
			{
				i++;
			}
		}

	}
			//printf("%d\t",nWords);

	return nWords;
}

thread_client.c

#include<stdlib.h>
#include<sys/socket.h>
#include<sys/types.h>       //pthread_t , pthread_attr_t and so on.
#include<stdio.h>
#include<netinet/in.h>      //structure sockaddr_in
#include<arpa/inet.h>       //Func : htonl; htons; ntohl; ntohs
#include<assert.h>          //Func :assert
#include<string.h>          //Func :memset bzero
#include<unistd.h>          //Func :close,write,read
#define SOCK_PORT 9988
#define BUFFER_LENGTH 1024
int main()
{
    int sockfd;
    int tempfd;
    struct sockaddr_in s_addr_in;
    char data_send[BUFFER_LENGTH];
    char data_recv[BUFFER_LENGTH];
    memset(data_send,0,BUFFER_LENGTH);
    memset(data_recv,0,BUFFER_LENGTH);
    sockfd = socket(AF_INET,SOCK_STREAM,0);       //ipv4,TCP
    if(sockfd == -1)
    {
        fprintf(stderr,"socket error!\n");
        exit(1);
    }
    //before func connect, set the attr of structure sockaddr.
    memset(&s_addr_in,0,sizeof(s_addr_in));
    s_addr_in.sin_addr.s_addr = inet_addr("127.0.0.1");      //trans char * to in_addr_t
    s_addr_in.sin_family = AF_INET;
    s_addr_in.sin_port = htons(SOCK_PORT);
    tempfd = connect(sockfd,(struct sockaddr *)(&s_addr_in),sizeof(s_addr_in));
    if(tempfd == -1)
    {
        fprintf(stderr,"Connect error! \n");
        exit(1);
    }
    while(1)
    {
    	printf("Please Input File Name On Server(input \"quit\" to quit):\t");
	scanf("%s", data_send);
	//gets(data_send);
        //scanf("%[^\n]",data_send);         //or you can also use this
        tempfd = write(sockfd,data_send,BUFFER_LENGTH);
        if(tempfd == -1)
        {
            fprintf(stderr,"write error\n");
            exit(0);
        }

        if(strcmp(data_send,"quit") == 0)  //quit,write the quit request and shutdown client
        {
            break;
        }
        else
        {
            tempfd = read(sockfd,data_recv,BUFFER_LENGTH);
            assert(tempfd != -1);
            printf("%s\n",data_recv);
            memset(data_send,0,BUFFER_LENGTH);
            memset(data_recv,0,BUFFER_LENGTH);
        }
	char buffer[BUFFER_LENGTH];
	int length=0;
   	bzero(buffer, BUFFER_LENGTH);
    	length = recv(sockfd, buffer, BUFFER_LENGTH, 0);
    	buffer[length] = '\0';
    	printf("count=%s\n", buffer);
    	bzero(buffer, BUFFER_LENGTH);
    }
    int ret = shutdown(sockfd,SHUT_WR);       //or you can use func close()--<unistd.h> to close the fd
    assert(ret != -1);
    return 0;
}

实验操作

• 性能比较：多线程一定程度上提高响应速度，在多核的情况下更能充分利用CPU资源

• 以下为实践内容
  
  

• 代码

并发程序-3

此次试验三因为时间原因，没有进行成功，我们先学习了一些知识。

如何调用进程？

1. 首先man -k thread|grep create查看
2. 找到函数，用man 3 pthread_create命令得到详细信息。

根据这个网址

http://blog.csdn.net/youbang321/article/details/7815707

了解到

功能：创建线程（实际上就是确定调用该线程函数的入口点），在线程创建以后，就开始运行相关的线程函数。

说明：thread：线程标识符；

          attr：线程属性设置；

          start_routine：线程函数的起始地址；

          arg：传递给start_routine的参数；

          返回值：成功，返回0；出错，返回-1。

感想

本次实验是基于网络编程基础的一次实验，与Windows环境下有很大的不同，并且加了很多其他的功能。实验过程中总体来说还是比较艰难的，因为时间和自己预习不充分的原因，使得部分没有完整做出来。

这个实验充分利用了我们网络编程中的知识，将课堂上讲的东西应用于实践中，使得我们对于客户端与服务器之间的通信有了比较好的认识，也对我们今后的学习有了实践的基础。