2018-2019-1 20165237 20165227 20165228 实验三 实时系统

---

No.1

实验要求：

• 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

实验截图

---

实验代码

客户端：#include
    
        // sockaddr_in#include
     
          // socket#include
      
          // socket#include
       
                // printf#include
        
                // exit#include
         
           // bzero#include
          
           #include
           
            #define SERVER_PORT 165237#define BUFFER_SIZE 1024#define FILE_NAME_MAX_SIZE 512int 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("The file name u want to send:\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("The 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;}服务器：#include
            
              // sockaddr_in#include
             
               // socket#include
              
                // socket#include
               
                 // printf#include
                
                  // exit#include
                 
                   // bzero#include
                  
                   #define SERVER_PORT 165237#define LENGTH_OF_LISTEN_QUEUE 20#define BUFFER_SIZE 1024#define FILE_NAME_MAX_SIZE 512int 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("oh yeah!! here: 5237:%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0FILE *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);}fclose(fp);return nWords;}int CountWordsInOneLine(const char *szLine){int nWords = 0;int i=0;for (;i
                  
                 
                
               
              
             
            
           
          
         
        
       
      
     
    

---

No.2

实验要求：

• 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

实验截图

---

服务器：#include
    
     #include
     
      #include
      
              //pthread_t , pthread_attr_t and so on.#include
       
        #include
        
               //structure sockaddr_in#include
         
           //Func : htonl; htons; ntohl; ntohs#include
          
            //Func :assert#include
           
             //Func :memset bzero#include
            
              //Func :close,write,read#define SOCK_PORT 5237#define BUFFER_LENGTH 1024#define MAX_CONN_LIMIT 512 //MAX connection limitstatic void Data_handle(void * sock_fd); //Only can be seen in the fileint 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("Loading...... \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("Connecting!!!!\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("Reloading......\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("Get something from the newclient : %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0FILE *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
             
              #include
              
               #include
               
                 //pthread_t , pthread_attr_t and so on.#include
                
                 #include
                 
                   //structure sockaddr_in#include
                  
                    //Func : htonl; htons; ntohl; ntohs#include
                   
                     //Func :assert#include
                    
                      //Func :memset bzero#include
                     
                       //Func :close,write,read#define SOCK_PORT 5237#define BUFFER_LENGTH 1024int 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 \"exit\" 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,"exit") == 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()--
                      
                        to close the fd assert(ret != -1); return 0;}
                      
                     
                    
                   
                  
                 
                
               
              
             
            
           
          
         
        
       
      
     
    

---

遇到的问题

-运行代码时出现对“pthread_create” 未定义的引用

• 解决方法：在gcc client.c 后 不能直接加-o ，而是

gcc client.c -lpthread -o client

---

对比线程

• 多线程与单线程的区别
  生活举例
  你早上上班，正要打卡的时候，手机响了。。你如果先接了电话，等接完了，在打卡，就是单线程。
  如果你一手接电话，一手打卡。就是多线程。
  2件事的结果是一样的。。你接了电话且打了卡。

多线程具有的优点:

因为用户界面可以在其它工作进行的同时一直处于活动状态，所以多线程技术会使程序的响应速度更快一点 ;当前如果没有正在进行处理的任务时，可以将处理器多余的时间让给其它任务;

多线程的缺点

等候使用共享资源时造成程序的运行速度变慢。这些共享资源主要是独占性的资源 ,如打印机等。对线程进行管理要求额外的 CPU开销。线程的使用会给系统带来上下文切换的额外负担。当这种负担超过一定程度时,多线程的特点主要表现在其缺点上,比如用独立的线程来更新数组内每个元素。线程的死锁。即较长时间的等待或资源竞争以及死锁等多线程症状。

---