Linux文件傳輸系統（文件的上傳，下載）

TCP協議下的文件傳輸

此程序是要實現linux下對文件的傳輸（上傳，下載）；包括對於Socket套接字的運用，對於目錄的操作，對於文件的操作。

成品演示：

運行時帶上倆個參數，ip以及端口；
輸入 list ：顯示某個目錄下的全部文件列表；
輸入get 文件名 ：下載文件；
輸入put 文件名 ：上傳；
輸入quit或者exit：退出；

程序流程框架圖

1，服務器端：

2，客戶端：

注意事項：

本代碼按照封裝思想，使主函數變得簡潔，容易理解和編寫；

服務器

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#define  N  128

// ./a.out 192.168.1.57 8000
// argv[0] argv[1]       aegv[2]

int process_list(int newsockfd,char *buf)
{

    DIR * dirp;
    int ret;
    struct dirent * direntp;
    dirp = opendir("./");
    if(dirp == NULL)
    {
        perror("opendir");
        exit(-1);
    }
    while( (direntp = readdir(dirp)) != NULL)
    {
        if(strncmp(direntp->d_name,".",1) == 0 ) continue; 
        strcpy(buf,direntp->d_name);
        ret = write(newsockfd,buf,N);
        if(ret < 0)
        {
            perror("write");
            exit(-1);
        }
    }
    close(newsockfd);


    return 0;
}
int process_get(int newsockfd,char *buf)
{

    int ret,fd,nbytes;

    fd = open(buf+4,O_RDWR);
    if(fd < 0)
    {
        perror("open");
        exit(-1);
    }
    while( (nbytes= read(fd,buf,N)) > 0)
    {
        ret = write(newsockfd,buf,nbytes);
        if(ret < 0)
        {
            perror("write");
            exit(-1);
        }
    }
    close(newsockfd);


    return 0;
}
int process_put(int newsockfd,char *buf)
{

    int ret,fd,nbytes;

    fd = open(buf+4,O_RDWR|O_CREAT|O_TRUNC,0664);
    if(fd < 0)
    {
        perror("open");
        exit(-1);
    }
    while( (nbytes= read(newsockfd,buf,N)) > 0)
    {
        ret = write(fd,buf,nbytes);
        if(ret < 0)
        {
            perror("write");
            exit(-1);
        }
    }
    close(newsockfd);
    close(fd);


    return 0;
}
int main(int argc, const char *argv[])
{
    char buf[N] ={0};
    int sockfd,ret,newsockfd;
    struct sockaddr_in myaddr,client;
    if(argc != 3)
    {
        printf("運行程序時帶入ip 和 port\n");
        exit(-1);
    }
    socklen_t addrlen = sizeof(client);
    sockfd = socket(AF_INET,SOCK_STREAM,0);
    if(sockfd < 0)
    {
        perror("socket");
        exit(-1);
    }
    printf("sockfd=%d\n",sockfd);
    memset(&myaddr,0,sizeof(myaddr));
    myaddr.sin_family = AF_INET ;
    myaddr.sin_port   = htons(atoi(argv[2]));
    myaddr.sin_addr.s_addr   = inet_addr(argv[1]); 
    ret = bind(sockfd,(struct sockaddr *)&myaddr,sizeof(myaddr)) ; // 給socket 一個固定的ip 和端口 
    if(ret < 0)
    {
        perror("bind");
        exit(-1);
    }
    ret = listen(sockfd,10);
    if(ret < 0)
    {
        perror("listen");
        exit(-1);
    }
    while(1)
    {
        newsockfd = accept(sockfd,(struct sockaddr *)&client,&addrlen) ; 
        if(newsockfd < 0)
        {
            printf("accept");
            exit(-1);
        }
        printf("newsockfd = %d\n",newsockfd);
        ret = read(newsockfd,buf,N);
        if(ret  < 0)
        {
            printf("read");
            exit(-1);
        }
        printf("buf=%s\n",buf);
        if( strncmp(buf,"list",4) == 0 ) 
        {
            process_list(newsockfd,buf);
        }
        else if( strncmp(buf,"get",3) == 0 ) 
        {
            process_get(newsockfd,buf);
        }
        else if( strncmp(buf,"put",3) == 0 ) 
        {
            process_put(newsockfd,buf);
        }
    }


    
    return 0;
}

客戶端

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

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#define  N  128 

// ./client 192.168.1.57 8000
// list 
// get file
// put file
// help

int process_list(struct sockaddr_in *addr,char * buf)
{
    int ret,sockfd,nbytes;
    sockfd = socket(AF_INET,SOCK_STREAM,0);
    if(sockfd < 0)
    {
        perror("socket");
        exit(-1);
    }
    ret = connect(sockfd,(struct sockaddr *)addr,sizeof(*addr)) ;
    if(ret < 0)
    {
        perror("connect");
        exit(-1);
    }
    ret = write(sockfd,buf,N);
    if(ret < 0)
    {
        perror("write");
        exit(-1);
    }
    while( (nbytes= read(sockfd,buf,N)) > 0)
    {
        printf("%s\n",buf);
    }
    close(sockfd);

    return 0;
}
int process_get(struct sockaddr_in *addr,char * buf)
{
    int ret,sockfd,nbytes,fd;
    sockfd = socket(AF_INET,SOCK_STREAM,0);
    if(sockfd < 0)
    {
        perror("socket");
        exit(-1);
    }
    ret = connect(sockfd,(struct sockaddr *)addr,sizeof(*addr)) ;
    if(ret < 0)
    {
        perror("connect");
        exit(-1);
    }
    ret = write(sockfd,buf,N);
    if(ret < 0)
    {
        perror("write");
        exit(-1);
    }
    fd = open(buf+4,O_RDWR|O_CREAT|O_TRUNC,0664);
    if(fd < 0)
    {
        perror("open");
        exit(-1);
    }
    while( (nbytes= read(sockfd,buf,N)) > 0)
    {
        ret = write(fd,buf,nbytes);
        if(ret < 0)
        {
            perror("write");
            exit(-1);
        }
    }
    close(sockfd);
    return 0;
}
int process_put(struct sockaddr_in *addr,char * buf)
{
    int ret,sockfd,nbytes,fd;
    sockfd = socket(AF_INET,SOCK_STREAM,0);
    if(sockfd < 0)
    {
        perror("socket");
        exit(-1);
    }
    ret = connect(sockfd,(struct sockaddr *)addr,sizeof(*addr)) ;
    if(ret < 0)
    {
        perror("connect");
        exit(-1);
    }
    ret = write(sockfd,buf,N);
    if(ret < 0)
    {
        perror("write");
        exit(-1);
    }
    fd = open(buf+4,O_RDWR);
    if(fd < 0)
    {
        perror("open");
        exit(-1);
    }
    while( (nbytes= read(fd,buf,N)) > 0)
    {
        ret = write(sockfd,buf,nbytes);
        if(ret < 0)
        {
            perror("write");
            exit(-1);
        }
    }
    close(sockfd);
    close(fd);
    return 0;
}
int main(int argc, const char *argv[])
{

    char buf[N] = {0};
    int sockfd,ret;
    struct sockaddr_in server,client;
    if(argc != 3)
    {
        printf("運行程序時帶入ip 和 port\n");
        exit(-1);
    }
    memset(&server,0,sizeof(server));
    server.sin_family = AF_INET ;
    server.sin_port   = htons( atoi(argv[2]) );
    server.sin_addr.s_addr   = inet_addr(argv[1]); 
    while(1)
    {
        printf(">:");
        fgets(buf,N,stdin);
        buf[strlen(buf)-1] = '\0';
        if( strncmp(buf,"list",4) == 0 ) 
        {
            process_list(&server,buf);
        }
        else if( strncmp(buf,"get",3) == 0 ) 
        {
            process_get(&server,buf);
        }
        else if( strncmp(buf,"put",3) == 0 ) 
        {
            process_put(&server,buf);
        }
        else if( strncmp(buf,"quit",4) == 0 ) 
        {
            break;
        }
        else if( strncmp(buf,"exit",4) == 0 ) 
        {
            break;
        }
        else 
        {
            printf("命令錯誤，請重新輸入\n");
        }
        
    }


#if 0 
    printf(">:");
    fgets(buf,N,stdin);
    ret  = write(sockfd,buf,N) ;
    if(ret < 0)
    {
        perror("write");
        exit(-1);
    }
    ret = read(sockfd,buf,N);
    if(ret  < 0)
    {
        printf("read");
        exit(-1);
    }
    printf("%s\n",buf);
    close(sockfd);


#endif
    
    return 0;
}

具體代碼就是這些；