/*TCP-echoサーバー

2009.11.5  Haruka Fukai*/

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

int main(int argc, char *argv[]){
  struct addrinfo hint={AI_PASSIVE,AF_INET6,SOCK_STREAM,0,0,NULL,NULL,NULL};
  socklen_t peerlen;
  struct addrinfo *ai,*res;
  struct sockaddr_in6 peer;
  int ret;
  int sock_fd,accept_fd;
  int client_addrlen;
  int readlen;
  struct sockaddr_in server,client;

  ret  = getaddrinfo(NULL,"8115",&hint,&res);
  if(ret!=0){
    perror("getaddrinfo");
    exit(0);
  }

  ai = res;
  /////socket/////
  sock_fd=socket(ai->ai_family,ai->ai_socktype,ai->ai_protocol); 
  if(sock_fd<0){
    perror("socket");
    exit(0);
  } 

  /////bind/////
  ret=bind(sock_fd,ai->ai_addr,ai->ai_addrlen);
  if(ret<0){
    perror("bind");
    exit(0);
  }
  
  /////listen/////
  ret=listen(sock_fd,5);
  if(ret<0){
    perror("listen");
    exit(0);
  }
  memset((void *)&client,0,sizeof(client));
  client_addrlen=sizeof(client);
  /////accept/////
  accept_fd=accept(sock_fd,(struct sockaddr *)&client,(socklen_t *)&client_addrlen);
  if(accept_fd<0){
    perror("accept");
    exit(0);
  }
  
  while(1){
    char buf[128];
    int readlen;
    int sendlen;
    char addrbuf[128];
    
    memset(buf,0,sizeof(buf));
    peerlen = sizeof(peer);
    readlen=recvfrom(accept_fd,buf,sizeof(buf),0,(struct sockaddr*)&peer,&peerlen);
    sendlen=sendto(accept_fd,buf,readlen,0,(struct sockaddr*)&peer,sizeof(struct sockaddr_in6));
  }
  
  freeaddrinfo(res);
  
  ret=close(accept_fd);
  if(ret<0){
    perror("close");
    exit(0);
  }
  
  ret=close(sock_fd);
  if(ret<0){
    perror("close");
    exit(0);
  }
  
  return 0;
}