/* Copyright (C) 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.

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

   The GNU C Library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <nss.h>
#include <netdb.h>
#include <errno.h>
#include <ctype.h>
#include <string.h>
#include <arpa/inet.h>
#include <bits/libc-lock.h>
#include <rpcsvc/nis.h>

#include "nss-nisplus.h"

__libc_lock_define_initialized (static, lock)

static nis_result *result = NULL;
static nis_name tablename_val = NULL;
static u_long tablename_len = 0;

#define NISENTRYVAL(idx,col,res) \
        ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_val)

#define NISENTRYLEN(idx,col,res) \
        ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_len)


static int
_nss_nisplus_parse_netent (nis_result *result, struct netent *network,
			    char *buffer, size_t buflen)
{
  char *first_unused = buffer;
  size_t room_left = buflen;
  unsigned int i;
  char *p, *line;

  if (result == NULL)
    return 0;

  if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) ||
      __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ ||
      strcmp(result->objects.objects_val[0].EN_data.en_type,
             "networks_tbl") != 0 ||
      result->objects.objects_val[0].EN_data.en_cols.en_cols_len < 3)
    return 0;

  if (NISENTRYLEN(0, 0, result) >= room_left)
    {
      /* The line is too long for our buffer.  */
    no_more_room:
      __set_errno (ERANGE);
      return -1;
    }

  strncpy (first_unused, NISENTRYVAL(0, 0, result),
           NISENTRYLEN (0, 0, result));
  first_unused[NISENTRYLEN(0, 0, result)] = '\0';
  network->n_name = first_unused;
  room_left -= (strlen (first_unused) +1);
  first_unused += strlen (first_unused) +1;
  network->n_addrtype = 0;
  network->n_net = inet_network (NISENTRYVAL (0, 2, result));
  p = first_unused;

  line = p;
  for (i = 0; i < result->objects.objects_len; i++)
    {
      if (strcmp (NISENTRYVAL (i, 1, result), network->n_name) != 0)
        {
          if (NISENTRYLEN (i, 1, result) + 2 > room_left)
	    goto no_more_room;

	  *p++ = ' ';
          p = __stpncpy (p, NISENTRYVAL (i, 1, result),
			 NISENTRYLEN (i, 1, result));
          *p = '\0';
          room_left -= (NISENTRYLEN (i, 1, result) + 1);
        }
    }
  ++p;
  first_unused = p;

  /* Adjust the pointer so it is aligned for
     storing pointers.  */
  first_unused += __alignof__ (char *) - 1;
  first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
  network->n_aliases = (char **) first_unused;
  if (room_left < 2 * sizeof (char *))
    goto no_more_room;
  room_left -= (2 * sizeof (char *));
  network->n_aliases[0] = NULL;

    i = 0;
  while (*line != '\0')
    {
      /* Skip leading blanks.  */
      while (isspace (*line))
        line++;

      if (*line == '\0')
        break;

      if (room_left < sizeof (char *))
	goto no_more_room;

      room_left -= sizeof (char *);
      network->n_aliases[i] = line;

      while (*line != '\0' && *line != ' ')
        ++line;

      if (line != network->n_aliases[i])
        {
          if (*line != '\0')
            {
              *line = '\0';
              ++line;
            }
          ++i;
        }
      else
        network->n_aliases[i] = NULL;
    }

  return 1;
}

static enum nss_status
_nss_create_tablename (void)
{
  if (tablename_val == NULL)
    {
      char buf [40 + strlen (nis_local_directory ())];
      char *p;

      p = __stpcpy (buf, "networks.org_dir.");
      p = __stpcpy (p, nis_local_directory ());
      tablename_val = __strdup (buf);
      if (tablename_val == NULL)
        return NSS_STATUS_TRYAGAIN;
      tablename_len = strlen (tablename_val);
    }
  return NSS_STATUS_SUCCESS;
}

enum nss_status
_nss_nisplus_setnetent (void)
{
  enum nss_status status = NSS_STATUS_SUCCESS;

  __libc_lock_lock (lock);

  if (result)
    nis_freeresult (result);
  result = NULL;

  if (tablename_val == NULL)
    if (_nss_create_tablename () != NSS_STATUS_SUCCESS)
      status = NSS_STATUS_UNAVAIL;

  __libc_lock_unlock (lock);

  return status;
}

enum nss_status
_nss_nisplus_endnetent (void)
{
  __libc_lock_lock (lock);

  if (result)
    nis_freeresult (result);
  result = NULL;

  __libc_lock_unlock (lock);

  return NSS_STATUS_SUCCESS;
}

static enum nss_status
internal_nisplus_getnetent_r (struct netent *network, char *buffer,
			       size_t buflen, int *herrnop)
{
  int parse_res;

  /* Get the next entry until we found a correct one. */
  do
    {
      nis_result *saved_res;

      if (result == NULL)
	{
	  saved_res = NULL;

	  if (tablename_val == NULL)
	    if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
	      return NSS_STATUS_UNAVAIL;

	  result = nis_first_entry(tablename_val);
	  if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
	    {
	      int retval;

	      retval = niserr2nss (result->status);
	      nis_freeresult (result);
	      result = NULL;
	      if (retval == NSS_STATUS_TRYAGAIN)
		{
		  *herrnop = NETDB_INTERNAL;
		  __set_errno (EAGAIN);
		  return retval;
		}
	      else
		return retval;
	    }
	}
      else
	{
	  nis_result *res;

	  res = nis_next_entry(tablename_val, &result->cookie);
	  saved_res = result;
	  result = res;
	  if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
	    {
	      int retval;

	      retval = niserr2nss (result->status);
	      nis_freeresult (result);
	      result = saved_res;
	      if (retval == NSS_STATUS_TRYAGAIN)
		{
		  *herrnop = NETDB_INTERNAL;
		  __set_errno (EAGAIN);
		}
	      return retval;
	    }
	}

      if ((parse_res = _nss_nisplus_parse_netent (result, network, buffer,
						  buflen)) == -1)
        {
          *herrnop = NETDB_INTERNAL;
          return NSS_STATUS_TRYAGAIN;
        }

    } while (!parse_res);

  return NSS_STATUS_SUCCESS;
}

enum nss_status
_nss_nisplus_getnetent_r (struct netent *result, char *buffer,
			   size_t buflen, int *herrnop)
{
  int status;

  __libc_lock_lock (lock);

  status = internal_nisplus_getnetent_r (result, buffer, buflen, herrnop);

  __libc_lock_unlock (lock);

  return status;
}

enum nss_status
_nss_nisplus_getnetbyname_r (const char *name, struct netent *network,
			      char *buffer, size_t buflen, int *herrnop)
{
  int parse_res, retval;

  if (tablename_val == NULL)
    if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
      return NSS_STATUS_UNAVAIL;

  if (name == NULL)
    {
      __set_errno (EINVAL);
      *herrnop = NETDB_INTERNAL;
      return NSS_STATUS_UNAVAIL;
    }
  else
    {
      nis_result *result;
      char buf[strlen (name) + 255 + tablename_len];

      /* Search at first in the alias list, and use the correct name
	 for the next search */
      sprintf(buf, "[name=%s],%s", name, tablename_val);
      result = nis_list(buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);

      /* If we do not find it, try it as original name. But if the
	 database is correct, we should find it in the first case, too */
      if ((result->status != NIS_SUCCESS &&
	   result->status != NIS_S_SUCCESS) ||
	  __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ ||
	  strcmp(result->objects.objects_val[0].EN_data.en_type,
		 "networks_tbl") != 0 ||
	  result->objects.objects_val[0].EN_data.en_cols.en_cols_len < 3)
	sprintf(buf, "[cname=%s],%s", name, tablename_val);
      else
	sprintf(buf, "[cname=%s],%s", NISENTRYVAL(0, 0, result),
		tablename_val);

      nis_freeresult (result);
      result = nis_list(buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);

      retval = niserr2nss (result->status);
      if (retval != NSS_STATUS_SUCCESS)
	{
	  if (retval == NSS_STATUS_TRYAGAIN)
	    {
	      __set_errno (EAGAIN);
	      *herrnop = NETDB_INTERNAL;
	    }
	  nis_freeresult (result);
	  return retval;
	}

      parse_res = _nss_nisplus_parse_netent (result, network, buffer, buflen);

      nis_freeresult (result);

      if (parse_res > 0)
	return NSS_STATUS_SUCCESS;

      *herrnop = NETDB_INTERNAL;
      if (parse_res == -1)
	return NSS_STATUS_TRYAGAIN;
      else
	return NSS_STATUS_NOTFOUND;
    }
}

/* XXX type is ignored, SUN's NIS+ table doesn't support it */
enum nss_status
_nss_nisplus_getnetbyaddr_r (const unsigned long addr, const int type,
			     struct netent *network,
			     char *buffer, size_t buflen, int *herrnop)
{
  if (tablename_val == NULL)
    if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
      return NSS_STATUS_UNAVAIL;

  {
    int parse_res, retval;
    nis_result *result;
    char buf[1024 + tablename_len];
    struct in_addr in;

    in = inet_makeaddr (addr, 0);
    sprintf (buf, "[addr=%s],%s", inet_ntoa (in), tablename_val);

    result = nis_list(buf, EXPAND_NAME, NULL, NULL);

    retval = niserr2nss (result->status);
    if (retval != NSS_STATUS_SUCCESS)
      {
	if (retval == NSS_STATUS_TRYAGAIN)
	  {
	    __set_errno (EAGAIN);
	    *herrnop = NETDB_INTERNAL;
	  }
	nis_freeresult (result);
	return retval;
      }

    parse_res = _nss_nisplus_parse_netent (result, network, buffer, buflen);

    nis_freeresult (result);

    if (parse_res > 0)
      return NSS_STATUS_SUCCESS;

    *herrnop = NETDB_INTERNAL;
    if (parse_res == -1)
      return NSS_STATUS_TRYAGAIN;
    else
      return NSS_STATUS_NOTFOUND;
  }
}