2019-2020 20175207- 20175235 third experiment real-time systems

20175207-20175235 third experiment real-time systems

20,175,207 cold south
20,175,235 Zeren La measures

table of Contents:

Concurrent Programs -1

Concurrent Program -2

Task details
learning to use Linux command wc (1)
designed and implemented based on Linux Socket program wc (1) server (port number is six after your student number) and client
client transfer a text file to the server
server back to add a text file the number of words
submitted the code above
accessory submit test shots, at least to test the attached two documents

• Experiment code:
  • Service-Terminal
    

   #include <stdio.h>
   #include <sys/types.h>
   #include <sys/socket.h>
   #include <netinet/in.h>
   #include <arpa/inet.h>
   #include <string.h>
  
   #define MYPORT 175235
  
   void main(){
   int serverfd, clientfd;
   struct sockaddr_in my_addr;
   struct sockaddr_in remote_addr;
  
   char buffer[BUFSIZ];
   memset(&my_addr, 0, sizeof(my_addr));
   my_addr.sin_family=AF_INET;
   my_addr.sin_addr.s_addr=INADDR_ANY;
   my_addr.sin_port=htons(MYPORT);
  
   if((serverfd=socket(PF_INET, SOCK_STREAM, 0))==-1){
       perror("socket");
   }
  
   if(bind(serverfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr))<0){
       perror("bind");
   }
   listen(serverfd, 5);
   int addrlen=sizeof(struct sockaddr_in);
   while(1){
       if((clientfd=accept(serverfd, (struct sockaddr *)&remote_addr, &addrlen))<0){
           perror("accept");
   }
   printf("accept client %s\n", inet_ntoa(remote_addr.sin_addr));
   int len, i;
   long wordscount=0;
   int flag=1;
   while(1){
       if((len=recv(clientfd, buffer, 1024, 0))>0){
           for(i=0; i<len; i++){
               if(flag==0){
                   switch(buffer[i]){
                       case ' ':
                           wordscount++;
                           break;
                       case '\n':
                           wordscount++;
                           break;
                       case '\r':
                           wordscount++;
                           break;
                       default:
                           break;
                   }
               }
           if(buffer[i]== ' ' || buffer[i]=='\n' || buffer[i]=='\r') flag=1;
           else flag=0;
           }
       }
       if(len<1024) break;
   }
   send(clientfd, &wordscount, sizeof(long), 0);
   close(clientfd);
   }
   close(serverfd);
  }

  • Client

  #include <stdio.h>  
  #include <sys/types.h>  
  #include <sys/socket.h>  
  #include <netinet/in.h>  
  #include <arpa/inet.h>  
  #include <string.h>
  
  #define MYPORT 175235
  
  void main(){
  int clientfd;
  struct sockaddr_in remote_addr;
  char buffer[BUFSIZ];
  memset(&remote_addr, 0 , sizeof(remote_addr));
  remote_addr.sin_family=AF_INET;
  remote_addr.sin_addr.s_addr=inet_addr("127.0.0.1");
  remote_addr.sin_port=htons(MYPORT);
  
  if((clientfd=socket(PF_INET,SOCK_STREAM,0))<0){  
      perror("socket");  
  }
  
  if(connect(clientfd, (struct sockaddr *)&remote_addr, sizeof(struct sockaddr))<0){
      perror("connect");
  }
  
  int len;
  FILE *fp;
  char path[20];
  gets(path);
  fp=fopen(path, "r");
  char readch;
  int i=0;
  while((readch=fgetc(fp))!=EOF){
      if(i<1024){
          buffer[i]=readch;
          i++;
      }
      else{
          i=0;
          int n=send(clientfd, buffer, 1024, 0);
      }
  }
  fclose(fp);
  if(i!=0) 
      send(clientfd, buffer, i, 0);
  long wordscount;
  recv(clientfd, &wordscount, sizeof(long), 0);
  printf("%ld\n", wordscount);
  close(clientfd);
  }

  
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Task details
using multithreading wc servers and use synchronous mutual exclusion mechanism to ensure the correct count
submit the above code
below to submit a test
comparing single-threaded version

Experiment code:

• Service-Terminal

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <pthread.h>

#define MYPORT 175235
pthread_mutex_t counter_mutex = PTHREAD_MUTEX_INITIALIZER;
int serverfd, clientfd;
char buffer[BUFSIZ];

void *wc(void *m){
    pthread_mutex_lock( &counter_mutex );
    int len, i;
    long wordscount=0;
    int flag=1;
    while(1){
        if((len=recv(clientfd, buffer, 1024, 0))>0){
            for(i=0; i<len; i++){
                if(flag==0){
                    switch(buffer[i]){
                        case ' ':
                            wordscount++;
                            break;
                        case '\n':
                            wordscount++;
                            break;
                        case '\r':
                            wordscount++;
                            break;
                        default:
                            break;
                    }
                }
                if(buffer[i]== ' ' || buffer[i]=='\n' || buffer[i]=='\r') 
                    flag=1;
                else 
                    flag=0;
            }
        }
        if(len<1024) 
            break;
    }
    send(clientfd, &wordscount, sizeof(long), 0);
    close(clientfd);
    pthread_mutex_unlock( &counter_mutex );
    return NULL;
}
void main(){
    pthread_t t;
    char arg[30];

    struct sockaddr_in my_addr;
    struct sockaddr_in remote_addr;

    memset(&my_addr, 0, sizeof(my_addr));
    my_addr.sin_family=AF_INET;
    my_addr.sin_addr.s_addr=INADDR_ANY;
    my_addr.sin_port=htons(MYPORT);

    if((serverfd=socket(PF_INET, SOCK_STREAM, 0))==-1){
        perror("socket");
    }

    if(bind(serverfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr))<0){
        perror("bind");
    }
    listen(serverfd, 5);
    int addrlen=sizeof(struct sockaddr_in);
    while(1){
        if((clientfd=accept(serverfd, (struct sockaddr *)&remote_addr, &addrlen))<0){
            perror("accept");
        }
        printf("accept client %s\n", inet_ntoa(remote_addr.sin_addr));
        pthread_create(&t, NULL, &wc, NULL);
        pthread_join(&t, NULL);
    }
    close(serverfd);
}

• Client

#include <stdio.h>  
#include <sys/types.h>  
#include <sys/socket.h>  
#include <netinet/in.h>  
#include <arpa/inet.h>  
#include <string.h>

#define MYPORT 175235

void main(){
    int clientfd;
    struct sockaddr_in remote_addr;
    char buffer[BUFSIZ];
    memset(&remote_addr, 0 , sizeof(remote_addr));
    remote_addr.sin_family=AF_INET;
    remote_addr.sin_addr.s_addr=inet_addr("127.0.0.1");
    remote_addr.sin_port=htons(MYPORT);

    if((clientfd=socket(PF_INET,SOCK_STREAM,0))<0){  
        perror("socket");  
    }

    if(connect(clientfd, (struct sockaddr *)&remote_addr, sizeof(struct sockaddr))<0){
        perror("connect");
    }

    int len;
    FILE *fp;
    char path[20];
    gets(path);
    fp=fopen(path, "r");
    char readch;
    int i=0;
    while((readch=fgetc(fp))!=EOF){
        if(i<1024){
            buffer[i]=readch;
            i++;
        }
        else{
            i=0;
            int n=send(clientfd, buffer, 1024, 0);
        }
    }
    fclose(fp);
    if(i!=0) 
        send(clientfd, buffer, i, 0);
    long wordscount;
    recv(clientfd, &wordscount, sizeof(long), 0);
    printf("%ld\n", wordscount);
    close(clientfd);
}

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