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/* A simple server to attach to
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netdb.h>
#define DUMP_WIDTH 16
static const char *name;
static int Socket(int p)
{
struct sockaddr_in addr;
int sock_fd;
if ((sock_fd=socket(AF_INET,SOCK_STREAM,0))==-1)
{
perror("socket");
exit(EXIT_FAILURE);
}
/* Bind port to address
*/
addr.sin_family=AF_INET;
addr.sin_addr.s_addr=INADDR_ANY;
addr.sin_port=htons(p);
if (bind(sock_fd,(void*)&addr,sizeof(addr))==-1)
{
perror("bind");
exit(EXIT_FAILURE);
}
if (listen(sock_fd,5)==-1)
{
perror("listen");
exit(EXIT_FAILURE);
}
return sock_fd;
}
static void Dump(const char *p, int len)
{
char asc[DUMP_WIDTH + 1] = {0};
unsigned int off = 0;
int col = 0;
while (len > 0)
{
unsigned char c = *p;
if (col == 0)
{
printf("%4.4x:", off);
}
printf(" %2.2x", (unsigned int)c);
asc[col++] = isprint(c) ? c : '.';
if (col == DUMP_WIDTH)
{
printf(" %s\n", asc);
memset(asc, 0, sizeof asc);
col = 0;
}
off++;
p++;
len--;
}
if (col > 0)
{
while (col++ < DUMP_WIDTH)
{
printf(" **");
}
printf(" %s\n", asc);
}
}
int main(int argc, char *argv[])
{
struct sockaddr_in addr;
char buff[1025];
int len;
socklen_t addrlen;
int sock_fd;
int connect_fd;
int ascii = 0;
name=argv[0];
if (argc<2)
{
fprintf(stderr,"%s: usage %s port [-a]\n", name, name);
exit(1);
}
ascii = (argc == 3 && strcmp(argv[2], "-a") == 0);
sock_fd = Socket((short)atoi(argv[1]));
printf("%s: socket bound\n",name);
while(1)
{
printf("%s: accepting\n",name);
if ((connect_fd=accept(sock_fd,NULL,0))==-1)
{
perror("accept");
exit(1);
}
addrlen=sizeof(addr);
if (getsockname(connect_fd,(void*)&addr,&addrlen)!=0)
{
perror("getsockname");
}
printf("%s: connection ON port %d\n",name,ntohs(addr.sin_port));
addrlen=sizeof(addr);
if (getpeername(connect_fd,(void*)&addr,&addrlen)!=0)
{
perror("getpeername");
}
printf("%s: connection FROM port %d\n",name,ntohs(addr.sin_port));
while((len=read(connect_fd,buff,1024))>0)
{
buff[len]=0;
if (ascii)
{
printf("%s", buff);
}
else
{
printf("%s: recieved\n",name);
Dump(buff, len);
}
}
if (len == -1)
{
perror("read");
}
close(connect_fd);
}
return EXIT_SUCCESS;
}
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