Linux网络编程6——使用TCP实现文件服务器

/*************************************************************************
  > File Name: server.c
  > Author: KrisChou
  > Mail:[email protected] 
  > Created Time: Thu 28 Aug 2014 09:40:32 PM CST
 ************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <netdb.h>
#define SNDSIZE 1024*1024 //1M，注意如果栈空间(可以设置的)没这么大，就用堆空间
#define FILE_NAME  "a.rmvb"

int main(int argc,char* argv[])// exe config
{
    /* 从配置文件中读取服务器联系方式：IP以及端口号 */
    int fd_conf ;
    fd_conf = open(argv[1], O_RDONLY) ;
    FILE* fp_conf = fdopen(fd_conf, "r"); //秀一下fdopen函数，文件描述符转换为文件指针 fdopen(int fd, const char *mode)
    char my_ip[32]="";
    int my_port ;
    fscanf(fp_conf, "%s%d", my_ip, &my_port);
    close(fd_conf);
    fclose(fp_conf);


    /* 创建服务器的监听socket端口 */
    int fd_listen
    fd_listen = socket(AF_INET, SOCK_STREAM, 0);
    if(fd_listen == -1)
    {
        perror("socket");
    }

    /* 为服务器socket端口绑定联系方式，以便让客户端connect */    
    struct sockaddr_in  server_addr ;
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET ;
    server_addr.sin_port = htons(my_port);
    server_addr.sin_addr.s_addr  = inet_addr(my_ip);
    if(-1 == bind(fd_listen, (struct sockaddr *)&server_addr, sizeof(server_addr)) )
    {
        perror("bind");
        close(fd_listen);
        exit(1);
    }
    /* listen */
    if(-1 == listen(fd_listen, 5))
    {
        perror("listen");
        close(fd_listen);
        exit(1);
    }
    
    /* accept */
    int fd_client;  /* 客户端socket端口的另一头 */
    struct sockaddr_in client_addr ; /* 客户端联系方式，以accept函数的传出参数给出 */
    int len ;
    memset(&client_addr, 0, sizeof(client_addr));
    len = sizeof(client_addr);
    while(1)
    {
        fd_client = accept(fd_listen, (struct sockaddr *)&client_addr, &len);
        if(fd_client == -1) 
        {
            continue ;
        }
        printf("a client connect ! ip:port  %s:%d\n",inet_ntoa(client_addr.sin_addr),ntohs(client_addr.sin_port));
        if(fork() == 0)
        {
            close(fd_listen); //对于子进程和孙子进程都不需要listen端口，直接关闭。
            if(fork() == 0)
            {

                int fd_file = open(FILE_NAME, O_RDONLY); //打开客户端要下载的文件
                char buf[SNDSIZE] ;
                int snd_cnt = 0 ;
                int readn ;
                /* 从文件中读取数据,并发送给客户端 */
                while(memset(buf, 0,SNDSIZE ), (readn = read(fd_file,buf, SNDSIZE)) > 0)
                {
                        if(send(fd_client, buf, readn, 0) != readn)
                        {
                            printf("send error! \n");
                        }
                        snd_cnt ++ ;
                }
                printf("send over: %d \n", snd_cnt);
                close(fd_file);
                close(fd_client);
                exit(0);
            }
            close(fd_client);
            exit(0);
        }
        close(fd_client);
        wait(NULL) ;

    }

    return 0 ;
}

/*************************************************************************
    > File Name: client.c
    > Author: KrisChou
    > Mail:[email protected] 
    > Created Time: Thu 28 Aug 2014 11:59:20 PM CST
 ************************************************************************/


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <netdb.h>
#define SNDSIZE 1024*1024
#define SERVER_PORT 6080 // 服务器端口

int main(int argc, char *argv[]) EXE IP
{
    /* socket */
    int fd_client;
    fd_client = socket(AF_INET, SOCK_STREAM, 0);
    if(fd_client == -1)
    {
        perror("socket");
        exit(1);
    }
    /* 存放所连服务器信息的结构体 */
    struct sockaddr_in server_addr;
    memset(&server_addr,0,sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(SERVER_PORT);
    server_addr.sin_addr.s_addr = inet_addr(argv[1]);
    /* connect */
    while(connect(fd_client, (struct sockaddr *)&server_addr,sizeof(server_addr)) == -1)
    {
        /* 当connect返回-1时，说明服务器还没有启动 */
        sleep(1);
        printf("connecting... \n");
    }
    printf("connect success! \n");

    int fd_write = open("txt", O_WRONLY | O_CREAT);//下载的内容写入本地文件中
    char buf[SNDSIZE];
    int readn;
    int recv_cnt = 0;
    while(memset(buf,0,SNDSIZE),(readn = recv(fd_client,buf,SNDSIZE,0)) > 0)
    {
        write(fd_write,buf,readn);
        recv_cnt++;
    }
    printf("recv over: %d \n", recv_cnt);
    close(fd_write);
    close(fd_client);
    return 0;
}