文件传输 【server.c + common.h + client.c】

#ifndef _COMM_H_
#define _COMM_H_

#define PORT 5566

#define CMD "%d\r\n"
#define COUNT "%d\r\n"
#define FNAME "%s\r\n"
#define FLEN "%d\r\n"

enum cmd_t {
    GET,
    LS,
    EXIT
};

#endif

#include <stdio.h>
#include <string.h>

#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>

#include <glob.h>

#include "comm.h"

#define BUFSIZE 1024
#define LEN 16

static struct sockaddr_in addr, peer;

void do_ls(FILE *fp)
{
    glob_t globbuf;
    int ret, i;
    char buf[BUFSIZE];

    ret = glob("./*.test", 0, NULL, &globbuf);
    if (ret != 0)
    {
        perror("glob");
    }
//COUNT="%d\r\n"；把找到匹配的路径个数按COUNT格式存进buf中
    sprintf(buf, COUNT, globbuf.gl_pathc);
//把匹配的路径个数写到套接字
    write(fileno(fp), buf, strlen(buf));
    for (i = 0; i < globbuf.gl_pathc; ++i)
    {
        sprintf(buf, FNAME, globbuf.gl_pathv[i]);
        write(fileno(fp), buf, strlen(buf));
    }
    fflush(fp);

    globfree(&globbuf);
}

void do_get(FILE *fp)
{
    char buf[BUFSIZE];
    char fname[BUFSIZE];
    int len, ch;
    FILE *src;
    struct stat stbuf;

printf("%s %d\n", __func__, __LINE__);
//从fp中读取一行放到buf中
    fgets(buf, BUFSIZE, fp);
//把buf中的数据按FNAME格式存进fname中
    sscanf(buf, FNAME, fname);
printf("%s %d\n", __func__, __LINE__);
//打开文件
    src = fopen(fname, "r");
printf("%s %d\n", __func__, __LINE__);
//获得文件信息
    stat(fname, &stbuf);
//文件大小
    len = stbuf.st_size;
//往自己终端打印文件大小
printf("flen = %d\n", len);
//把文件大小按FLEN格式发送给对方
    fprintf(fp, FLEN, len);
    fflush(fp);
//发送文件内容
    while ((ch = fgetc(src)) != EOF)
    {
        fputc(ch, fp);
    }
    fflush(fp);
}

void do_server_job(int sd)
{
    FILE *fp;
    int cmd, ret;
    int flag;
    char buf[BUFSIZE];
//打开套接字
    fp = fdopen(sd, "r+");
    if (fp == NULL)
    {
        perror("fdopen");
        return;
    }

    flag = 1;
    while (flag)
    {
        ret = read(fileno(fp), buf, BUFSIZE);
        if (ret == 0)
        {
            break;
        }
        buf[ret] = '\0';
//把buf按"%d\r\n"存进cmd中
        sscanf(buf, "%d\r\n", &cmd);
printf("%s %d, cmd = %d, GET = %d\n", __func__, __LINE__, cmd, GET);

        switch(cmd)
        {
        case LS:
            do_ls(fp);
            break;

        case GET:
printf("%s %d\n", __func__, __LINE__);
            do_get(fp);
printf("%s %d\n", __func__, __LINE__);
            break;

        case EXIT:
            flag = 0;
            break;
        }
    }
}

int main(void)
{
    int listen_fd, connect_fd;
    int len, ret;
    char ip4str[LEN];

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

    addr.sin_family = AF_INET;
    addr.sin_port = htons(PORT);
    inet_pton(AF_INET, "0.0.0.0", &addr.sin_addr);

    ret = bind(listen_fd, (struct sockaddr *)&addr, sizeof(addr));
    if (ret == -1)
    {
        perror("bind");
        return -1;
    }

    ret = listen(listen_fd, 10);
    if (ret == -1)
    {
        perror("listen");
        return -1;
    }

    while (1)
    {
        len = sizeof(peer);
        connect_fd = accept(listen_fd,
                            (struct sockaddr *)&peer,
                            &len);
        if (connect_fd == -1)
        {
            perror("accept");
            return -1;
        }

        inet_ntop(AF_INET, &peer.sin_addr, ip4str, LEN);
        printf("Serving %s %d ...\n",
               ip4str, ntohs(peer.sin_port));

        if (fork() == 0)
        {
            close(listen_fd);
            do_server_job(connect_fd);
            close(connect_fd);

            printf("Exit %s %d ...\n",
                   ip4str, ntohs(peer.sin_port));
            return 0;
        }
        close(connect_fd);
    }

    return 0;
}

#include <stdio.h>
#include <string.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/ip.h>

#include <unistd.h>

#include "comm.h"

#define BUFSIZE 1024
#define LEN 16

static struct sockaddr_in addr, peer;

void do_ls(FILE *fp)
{
    int count;
    int i;
    char fname[BUFSIZE];
    char buf[BUFSIZE];
//发送LS
    fprintf(fp, CMD, LS);
    fflush(fp);
//从套接字中读到路径名个数
    fscanf(fp, COUNT, &count);
//取字符；格式转换；打印出来
    for (i = 0; i < count; ++i)
    {
        fgets(buf, BUFSIZE, fp);
        sscanf(buf, FNAME, fname);
        printf(" %s\n", fname);
    }
}

void do_exit(FILE *fp)
{//发送EXIT
    fprintf(fp, CMD, EXIT);
    fflush(fp);
}

void do_get(FILE *fp, char *fname)
{
    char buf[BUFSIZE];
    int len, ch, i;
    FILE *dst;

    dst = fopen(fname, "w");
//发送GET
    fprintf(fp, CMD, GET);
    fflush(fp);
//把文件名按FNAME格式写到套接字中
    fprintf(fp, FNAME, fname);
    fflush(fp);
//得到文件大小
    fgets(buf, BUFSIZE, fp);
//把字符转为整数
    sscanf(buf, FLEN, &len);
printf("len = %d\n", len);

    for (i = 0; i < len; ++i)
    {
        ch = fgetc(fp);
        fputc(ch, dst);
    }

    fclose(dst);
}

void do_client_job(int sd)
{
    char line[BUFSIZE];
    int ret;
    FILE *fp;

    fp = fdopen(sd, "r+");
    if (fp == NULL)
    {
        perror("fdopen");
        return;
    }

    while (1)
    {
        printf("myftp: ");

        fgets(line, BUFSIZE, stdin);
        line[strlen(line) - 1] = '\0';

        if (strcmp(line, "ls") == 0)
        {
            do_ls(fp);
        }
        else if (strncmp(line, "get ", 4) == 0)
        {
            do_get(fp, line + 4);
        }
        else if (strcmp(line, "exit") == 0)
        {
            do_exit(fp);
            break;
        }
    }
}

int main(int argc, char *argv[])
{
    int sd, ret, stamp;
    struct sockaddr_in addr;
    FILE *fp;

    if (argc < 3)
    {
        fprintf(stderr, "Usage: %s addr port.\n",
                argv[0]);
        return -1;
    }

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

    addr.sin_family = AF_INET;
    addr.sin_port = htons(atoi(argv[2]));
    inet_pton(AF_INET, argv[1], &addr.sin_addr);

    ret = connect(sd, (struct sockaddr *)&addr, sizeof(addr));
    if (ret == -1)
    {
        perror("connect");
        return -1;
    }

    do_client_job(sd);

    close(sd);

    return 0;
}