我要么很累,不能注意到一些简单的事情,要么就是完全搞砸了我。我遇到了分段错误(核心转储),我已经设法将它指向worker函数中的sendto()。 (服务器)C并发UDP套接字,奇怪的分段错误
Server代码:
//UDPServer.c
/*
* gcc -o server UDPServer.c
* ./server <port> <buffersize>
*/
#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
void err(char *str)
{
perror(str);
exit(1);
}
int sock;
typedef struct
{
struct sockaddr_in client;
int buffsize;
char *msg;
} data;
void *worker (void* asd)
{
int len;
FILE *fp;
data d;
d = *(data*) asd;
char buff[d.buffsize];
printf("Received packet from %s:%d\nData:%sSize:%d\n",
inet_ntoa(d.client.sin_addr), ntohs(d.client.sin_port)
,d.msg,d.buffsize);
char * fn;
memcpy (fn,d.msg,strlen(d.msg)-1);
fp = fopen(fn,"rb");
int bytes;
len = sizeof(d.client);
printf ("%d\n",len);
while (bytes=fread(buff,sizeof(char),d.buffsize,fp))
{
printf ("Server sent %d bytes.\n",bytes);
-> this if right here. this causes the core dump when attempting to send
if(sendto(sock , &buff , sizeof(buff),0,(struct sockaddr *)&d.client,len)<0)
err("Error sending.");
}
fclose(fp);
}
int main(int argc, char** argv)
{
struct sockaddr_in server, client;
int port, i;
socklen_t slen=sizeof(client);
if(argc != 3)
{
printf("Usage: <Port> <Bytes>\n");
exit(0);
}
else
sscanf(argv[1],"%d",&port);
int buffsize = atoi(argv[2]);
char buff[buffsize];
if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
err("socket");
else
printf("Server : Socket() successful\n");
bzero(&server, sizeof(server));
server.sin_family = AF_INET;
server.sin_port = htons(port);
server.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(sock, (struct sockaddr*) &server, sizeof(server))==-1)
err("bind");
else
printf("Server : bind() successful\n");
while(1)
{
memset(&buff,0,sizeof(buff));
if (recvfrom(sock, &buff, sizeof(buff), 0, (struct sockaddr*)&client, &slen)==-1)
err("recvfrom()");
data d;
d.client = client;
d.buffsize = buffsize;
d.msg = buff;
pthread_t t;
pthread_create(&t,NULL,worker,&d);
pthread_join(t,NULL);
}
return 0;
}
我不认为客户端是与此有关,因为它是唯一的工作是送的文件名。阅读作品顺便说一句,我测试过了。
无论如何,我只是试图发送文件的内容的那一刻。我一直想弄清楚过去一小时和我的生活,我无法找出它是什么问题。分段错误对我来说毫无意义。
任何建议,非常感谢。
buffsize非常大(例如超过几千字节)?如果是这样,您可能会占用比分配给工作线程更多的堆栈空间。传统的解决方案是分配堆上的缓冲区。 –