multiplex.c

Path MPICH-V for MPICH the MPI Implementation

/*
  MPICH-V2
  Copyright (C) 2002, 2003 Groupe Cluster et Grid, LRI, Universite de Paris Sud


  This file is part of MPICH-V2.

  MPICH-V2 is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  MPICH-V2 is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with MPICH-V2; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  $Id: multiplex.c,v 1.1.1.1 2004/01/30 15:49:38 lemarini Exp $
*/
#include<sys/types.h>
#include<sys/socket.h>
#include<sys/time.h>
#include<netinet/in.h>
#include<ctype.h>
#include<netdb.h>
#include<errno.h>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include <arpa/inet.h>
#include <unistd.h>

#define MTU 65536


static int uread(int sock,char * buf,int size)
{
  int n,rd=0;
  while(rd<size) 
    {
      n=recv(sock, buf+rd, size-rd, 0);
      if(n<=0)
	{
	  if((n<0) && ((errno == EINTR) || (errno == EAGAIN))) 
	    continue;
	  return n;
	}
      rd+=n;
    }
  return rd;
}


typedef struct client {  
  struct sockaddr_in connect_info;
  int fd;
  struct client *next;
} client; 



int main(int argc,char **argv)
{
  int soc;
  struct sockaddr_in server;
  struct sockaddr_in s_client;
  client *cl=NULL;
  int size_client;
  int taille;
  char buf[MTU];
  int i;
  struct timeval tv;
  fd_set readset;
  int maxfd;
  client *nc;
  client *tmp;
  
  if (argc<2)
    {
      fprintf(stderr,"usage : %s port\n",argv[0]);
      exit(0);
    }
  
  /* creation de la socket */
  if ((soc=socket(AF_INET,SOCK_STREAM,0))<0)
    {
      perror("socket");
      exit(1);
    }
  
  
  /* remplissage de la structure de description de connexion */
  bzero(&server,sizeof(server));
  server.sin_family=AF_INET;
  server.sin_addr.s_addr=INADDR_ANY;
  server.sin_port=htons(atoi(argv[1]));
			
  /* binding de la socket */
  if (bind(soc,(struct sockaddr*) &server,sizeof(server))<0)
    {
      perror("bind");
      exit(1);
    }
  
  /* passage de la socket en mode listen */
  if (listen(soc,32)<0)
    {
      perror("listen");
      exit(1);
    }
  for(;;)
    {
      maxfd=0;
      FD_ZERO(&readset);
      tmp=cl;
      while(tmp)
	{
	  if (tmp->fd>0)
	    FD_SET(tmp->fd,&readset);
	  if (tmp->fd>maxfd)
	    maxfd=tmp->fd;
	  tmp=tmp->next;
	}
      FD_SET(soc,&readset);
      if (soc>maxfd)
	maxfd=soc;
      maxfd++;
      select(maxfd,&readset,NULL,NULL,NULL);

      if (FD_ISSET(soc,&readset))
	{
	  nc=(client *)calloc(1,sizeof(client));
	  if ((nc->fd=accept(soc,(struct sockaddr *)&s_client,(socklen_t *)&size_client))<0)
	    {
	      fprintf(stderr,"accept : %d\n",errno);
	      perror("accept");
	      exit(1);
	    }
	  gettimeofday(&tv,NULL);
	  memcpy(&nc->connect_info,&s_client,size_client);
	  printf("[%ld.%ld:%s:E]\n",tv.tv_sec,tv.tv_usec,inet_ntoa(nc->connect_info.sin_addr));
	  fflush(stdout);
	  if (cl==NULL)
	    cl=nc;
	  else
	    {
	      nc->next=cl;
	      cl=nc;
	    }
	}
  
      tmp=cl;
      while(tmp)
	{
	  if ((tmp->fd>0) && (FD_ISSET(tmp->fd,&readset)))
	    {
	      bzero(buf,MTU);
	      if (uread(tmp->fd,buf,4)<=0)
		{
		  perror("uread1");
		  gettimeofday(&tv,NULL);
		  printf("[%ld.%ld:%s:D]\n",tv.tv_sec,tv.tv_usec,inet_ntoa(tmp->connect_info.sin_addr));
		  fflush(stdout);
		  tmp->fd=-1;
		  break;
		}
	      taille=ntohl(*(int *)buf);
	      if (taille>MTU)
		{
		  fprintf(stderr,"MTU too little (requested size=%08x)\n",taille);
		  printf("[%ld.%ld:%s:B]\n",tv.tv_sec,tv.tv_usec,inet_ntoa(tmp->connect_info.sin_addr));
		  fflush(stdout);
		  close(tmp->fd);
		  tmp->fd=-1;
		  break;
		}
	  
	      bzero(buf,MTU);
	      if (uread(tmp->fd,buf,taille)<=0)
		{
		  perror("uread2");
		  gettimeofday(&tv,NULL);
		  printf("[%ld.%ld:%s:B]\n",tv.tv_sec,tv.tv_usec,inet_ntoa(tmp->connect_info.sin_addr));
		  fflush(stdout);
		  tmp->fd=-1;
		  break;
		}
	  
	      for(i=0;i<taille;i++)
		{
		  if (buf[i]=='\n')
		    buf[i]=' ';
		}
	      printf("[%ld.%ld:%s:M]%s\n",tv.tv_sec,tv.tv_usec,inet_ntoa(tmp->connect_info.sin_addr),buf);
	      fflush(stdout);
	    }
	  tmp=tmp->next;
	}
    }
}