
/***************************************************************************
 * netutils.c -- This contains some useful little network/socket related   *
 * utility functions.                                                      *
 *                                                                         *
 ***********************IMPORTANT NSOCK LICENSE TERMS***********************
 *                                                                         *
 * The nsock parallel socket event library is (C) 1999-2009 Insecure.Com   *
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 * may be willing to sell alternative licenses (contact                    *
 * sales@insecure.com ).                                                   *
 *                                                                         *
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 * OpenSSL library which is distributed under a license identical to that  *
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 * but you are not obligated to do so.                                     *
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 * have been found so far).                                                *
 *                                                                         *
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 *                                                                         *
 ***************************************************************************/

/* $Id: netutils.c 12775 2009-03-31 04:14:45Z fyodor $ */

#include "netutils.h"
#include "error.h"

#if WIN32
#include "Winsock2.h"
#endif

#if HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#if HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif

static int netutils_debugging = 0;

/* maximize the number of file descriptors (including sockets) allowed
   for this process and return that maximum value (note -- you better
   not actually open this many -- stdin, stdout, other files opened by
   libraries you use, etc. all count toward this limit.  Leave a
   little slack */

int maximize_fdlimit() { 
#ifndef WIN32

struct rlimit r; 
static int maxfds = -1;

  if (maxfds > 0)
    return maxfds;

#if(defined(RLIMIT_NOFILE))
  if (!getrlimit(RLIMIT_NOFILE, &r)) {
    r.rlim_cur = r.rlim_max;
    if (setrlimit(RLIMIT_NOFILE, &r))
      if (netutils_debugging) perror("setrlimit RLIMIT_NOFILE failed");
    if (!getrlimit(RLIMIT_NOFILE, &r)) {
      maxfds = r.rlim_cur;
      return maxfds;
    } else return 0;
  }
#endif
#if(defined(RLIMIT_OFILE) && !defined(RLIMIT_NOFILE))
  if (!getrlimit(RLIMIT_OFILE, &r)) {
    r.rlim_cur = r.rlim_max;
    if (setrlimit(RLIMIT_OFILE, &r))
      if (netutils_debugging) perror("setrlimit RLIMIT_OFILE failed");
    if (!getrlimit(RLIMIT_OFILE, &r)) {
      maxfds = r.rlim_cur;
      return maxfds;
    } else return 0;
  }
#endif
#endif /* !WIN32 */
  return 0;
}

