c - 使用C中的套接字将文件从客户端发送到服务器

Question

程序应该将文件的内容从客户端发送到服务器端的输出文件。但是，我的代码适用于少数文件，不适用于大多数文件。例如，如果我尝试将名为 morefood.txt 的文件的内容复制到输出文件 picolo.txt，则不会复制任何内容。

服务器代码:

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

int main(int argc, char *argv[]){

  int fd =0, confd = 0;
  struct sockaddr_in serv_addr;

  char buff[1025];
  int num;

  fd = socket(AF_INET, SOCK_STREAM, 0);
  printf("Socket created\n");

  memset(&serv_addr, '0', sizeof(serv_addr));
  memset(buff, '0', sizeof(buff));

  serv_addr.sin_family = AF_INET;
  serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
  serv_addr.sin_port = htons(5000);

  bind(fd, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
  listen(fd, 10);

  FILE* fp = fopen( "picolo.txt", "wb");

  if(fp == NULL){
      fprintf(stderr, "something went south");
      return 1;
  }

  while(1){

      confd = accept(fd, (struct sockaddr*)NULL, NULL);

      char recvbuff[10];

      int b = recv(confd, recvbuff, 10, 0);

      while(b>0)
     {
          fwrite(recvbuff, 1, b, fp);

          b = recv(confd, recvbuff, 10, 0);

     }
   close(confd);
  }

return 0;

}

客户端代码:

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


int main(int argc, char *argv[]){

    int sfd =0, n=0;
    char rbuff[1024];

    struct sockaddr_in serv_addr;

    memset(rbuff, '0', sizeof(rbuff));
    sfd = socket(AF_INET, SOCK_STREAM, 0);

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(5000);
    serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");

    connect(sfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));

    FILE *fp = fopen("morefood.txt", "rb");

    if(fp == NULL){
        fprintf(stderr, "oh no!");
        return 1;
    }

    char sendbuffer[100];

    int b = fread(sendbuffer, 1, sizeof(sendbuffer), fp);

    while(!feof(fp)){
        send(sfd, sendbuffer, b, 0);
        b = fread(sendbuffer, sizeof(sendbuffer), 1, fp);
    }

    return 0;

   }

Answer 1

问题是传输和接收循环都被窃听了!我以代码运行得更好的方式修改了它们，但我认为要修改很多代码才能获得可靠的代码!

客户:

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

int main(int argc, char *argv[]){

    int sfd =0, n=0, b;
    char rbuff[1024];
    char sendbuffer[100];

    struct sockaddr_in serv_addr;

    memset(rbuff, '0', sizeof(rbuff));
    sfd = socket(AF_INET, SOCK_STREAM, 0);

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(5000);
    serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");

    b=connect(sfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
    if (b==-1) {
        perror("Connect");
        return 1;
    }

    FILE *fp = fopen("prova.jpg", "rb");
    if(fp == NULL){
        perror("File");
        return 2;
    }

    while( (b = fread(sendbuffer, 1, sizeof(sendbuffer), fp))>0 ){
        send(sfd, sendbuffer, b, 0);
    }

    fclose(fp);
    return 0;

}

服务器:

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

int main(int argc, char *argv[]){

    int fd =0, confd = 0,b,tot;
    struct sockaddr_in serv_addr;

    char buff[1025];
    int num;

    fd = socket(AF_INET, SOCK_STREAM, 0);
    printf("Socket created\n");

    memset(&serv_addr, '0', sizeof(serv_addr));
    memset(buff, '0', sizeof(buff));

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(5000);

    bind(fd, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
    listen(fd, 10);

    while(1){
        confd = accept(fd, (struct sockaddr*)NULL, NULL);
        if (confd==-1) {
            perror("Accept");
            continue;
        }
        FILE* fp = fopen( "provacopy.jpg", "wb");
        tot=0;
        if(fp != NULL){
            while( (b = recv(confd, buff, 1024,0))> 0 ) {
                tot+=b;
                fwrite(buff, 1, b, fp);
            }

            printf("Received byte: %d\n",tot);
            if (b<0)
               perror("Receiving");

            fclose(fp);
        } else {
            perror("File");
        }
        close(confd);
    }

    return 0;
}