/* Copyright (C) 1996-2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Thorsten Kukuk <kukuk@suse.de>, 1996.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; 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 <ctype.h>
#include <errno.h>
#include <string.h>
#include <bits/libc-lock.h>
#include <rpcsvc/yp.h>
#include <rpcsvc/ypclnt.h>

#include "nss-nis.h"


/* Get the declaration of the parser function.  */
#define ENTNAME servent
#define EXTERN_PARSER
#include <nss/nss_files/files-parse.c>

__libc_lock_define_initialized (static, lock)

struct response_t
{
  struct response_t *next;
  char val[0];
};

struct intern_t
{
  struct response_t *start;
  struct response_t *next;
};
typedef struct intern_t intern_t;

static intern_t intern = { NULL, NULL };

struct search_t
{
  const char *name;
  const char *proto;
  int port;
  enum nss_status status;
  struct servent *serv;
  char *buffer;
  size_t buflen;
  int *errnop;
};

static int
saveit (int instatus, char *inkey, int inkeylen, char *inval,
        int invallen, char *indata)
{
  intern_t *intern = (intern_t *) indata;

  if (instatus != YP_TRUE)
    return instatus;

  if (inkey && inkeylen > 0 && inval && invallen > 0)
    {
      struct response_t *newp = malloc (sizeof (struct response_t)
					+ invallen + 1);
      if (newp == NULL)
	return YP_FALSE; /* We have no error code for out of memory */

      if (intern->start == NULL)
	intern->start = newp;
      else
	intern->next->next = newp;
      intern->next = newp;

      newp->next = NULL;
      *((char *) mempcpy (newp->val, inval, invallen)) = '\0';
    }

  return 0;
}

static int
dosearch (int instatus, char *inkey, int inkeylen, char *inval,
	  int invallen, char *indata)
{
  struct search_t *req = (struct search_t *) indata;

  if (instatus != YP_TRUE)
    return 1;

  if (inkey && inkeylen > 0 && inval && invallen > 0)
    {
      struct parser_data *pdata = (void *) req->buffer;
      int parse_res;
      char *p;

      if ((size_t) (invallen + 1) > req->buflen)
	{
	  *req->errnop = ERANGE;
	  req->status = NSS_STATUS_TRYAGAIN;
	  return 1;
	}

      p = strncpy (req->buffer, inval, invallen);
      req->buffer[invallen] = '\0';
      while (isspace (*p))
        ++p;

      parse_res = _nss_files_parse_servent (p, req->serv, pdata, req->buflen,
					    req->errnop);
      if (parse_res == -1)
	{
	  req->status = NSS_STATUS_TRYAGAIN;
	  return 1;
	}

      if (!parse_res)
        return 0;

      if (req->proto != NULL && strcmp (req->serv->s_proto, req->proto) != 0)
	return 0;

      if (req->port != -1 && req->serv->s_port != req->port)
	return 0;

      if (req->name != NULL && strcmp (req->serv->s_name, req->name) != 0)
	{
	  char **cp;
	  for (cp = req->serv->s_aliases; *cp; cp++)
	    if (strcmp (req->name, *cp) == 0)
	      break;

	  if (*cp == NULL)
	    return 0;
	}

      req->status = NSS_STATUS_SUCCESS;
      return 1;
    }

  return 0;
}

static enum nss_status
internal_nis_endservent (intern_t * intern)
{
  while (intern->start != NULL)
    {
      intern->next = intern->start;
      intern->start = intern->start->next;
      free (intern->next);
    }

  return NSS_STATUS_SUCCESS;
}

enum nss_status
_nss_nis_endservent (void)
{
  enum nss_status status;

  __libc_lock_lock (lock);

  status = internal_nis_endservent (&intern);

  __libc_lock_unlock (lock);

  return status;
}

static enum nss_status
internal_nis_setservent (intern_t *intern)
{
  char *domainname;
  struct ypall_callback ypcb;
  enum nss_status status;

  if (yp_get_default_domain (&domainname))
    return NSS_STATUS_UNAVAIL;

  (void) internal_nis_endservent (intern);

  ypcb.foreach = saveit;
  ypcb.data = (char *) intern;
  status = yperr2nss (yp_all (domainname, "services.byname", &ypcb));
  intern->next = intern->start;

  return status;
}

enum nss_status
_nss_nis_setservent (int stayopen)
{
  enum nss_status status;

  __libc_lock_lock (lock);

  status = internal_nis_setservent (&intern);

  __libc_lock_unlock (lock);

  return status;
}

static enum nss_status
internal_nis_getservent_r (struct servent *serv, char *buffer,
			   size_t buflen, int *errnop, intern_t *data)
{
  struct parser_data *pdata = (void *) buffer;
  int parse_res;
  char *p;

  if (data->start == NULL)
    internal_nis_setservent (data);

  /* Get the next entry until we found a correct one. */
  do
    {
      if (data->next == NULL)
	return NSS_STATUS_NOTFOUND;

      p = strncpy (buffer, data->next->val, buflen);
      while (isspace (*p))
        ++p;

      parse_res = _nss_files_parse_servent (p, serv, pdata, buflen, errnop);
      if (parse_res == -1)
        return NSS_STATUS_TRYAGAIN;
      data->next = data->next->next;
    }
  while (!parse_res);

  return NSS_STATUS_SUCCESS;
}

enum nss_status
_nss_nis_getservent_r (struct servent *serv, char *buffer, size_t buflen,
		       int *errnop)
{
  enum nss_status status;

  __libc_lock_lock (lock);

  status = internal_nis_getservent_r (serv, buffer, buflen, errnop, &intern);

  __libc_lock_unlock (lock);

  return status;
}

enum nss_status
_nss_nis_getservbyname_r (const char *name, const char *protocol,
			  struct servent *serv, char *buffer, size_t buflen,
			  int *errnop)
{
  enum nss_status status;
  char *domain;

  if (name == NULL)
    {
      *errnop = EINVAL;
      return NSS_STATUS_UNAVAIL;
    }

  if (yp_get_default_domain (&domain))
    return NSS_STATUS_UNAVAIL;

  /* If the protocol is given, we could try if our NIS server knows
     about services.byservicename map. If yes, we only need one query.
     If the protocol is not given, try first name/tcp, then name/udp
     and then fallback to sequential scanning of services.byname map.  */
  const char *proto = protocol != NULL ? protocol : "tcp";
  do
    {
      char key[strlen (name) + strlen (proto) + 2];
      char *cp, *result;
      size_t keylen, len;
      int int_len;

      /* key is: "name/proto" */
      cp = stpcpy (key, name);
      *cp++ = '/';
      stpcpy (cp, proto);
      keylen = strlen (key);
      status = yperr2nss (yp_match (domain, "services.byservicename", key,
				    keylen, &result, &int_len));
      len = int_len;

      /* If we found the key, it's ok and parse the result. If not,
	 fall through and parse the complete table. */
      if (status == NSS_STATUS_SUCCESS)
	{
	  struct parser_data *pdata = (void *) buffer;
	  int parse_res;
	  char *p;

	  if ((size_t) (len + 1) > buflen)
	    {
	      free (result);
	      *errnop = ERANGE;
	      return NSS_STATUS_TRYAGAIN;
	    }

	  p = strncpy (buffer, result, len);
	  buffer[len] = '\0';
	  while (isspace (*p))
	    ++p;
	  free (result);
	  parse_res = _nss_files_parse_servent (p, serv, pdata,
						buflen, errnop);
	  if (parse_res < 0)
	    {
	      if (parse_res == -1)
		return NSS_STATUS_TRYAGAIN;
	      else
		return NSS_STATUS_NOTFOUND;
	    }
	  else
	    return NSS_STATUS_SUCCESS;
	}
    }
  while (protocol == NULL && (proto[0] == 't' ? (proto = "udp") : NULL));

  struct ypall_callback ypcb;
  struct search_t req;

  ypcb.foreach = dosearch;
  ypcb.data = (char *) &req;
  req.name = name;
  req.proto = protocol;
  req.port = -1;
  req.serv = serv;
  req.buffer = buffer;
  req.buflen = buflen;
  req.errnop = errnop;
  req.status = NSS_STATUS_NOTFOUND;
  status = yperr2nss (yp_all (domain, "services.byname", &ypcb));

  if (status != NSS_STATUS_SUCCESS)
    return status;

  return req.status;
}

enum nss_status
_nss_nis_getservbyport_r (int port, const char *protocol,
			  struct servent *serv, char *buffer,
			  size_t buflen, int *errnop)
{
  enum nss_status status;
  char *domain;

  if (yp_get_default_domain (&domain))
    return NSS_STATUS_UNAVAIL;

  /* If the protocol is given, we only need one query.
     Otherwise try first port/tcp, then port/udp and then fallback
     to sequential scanning of services.byname.  */
  const char *proto = protocol != NULL ? protocol : "tcp";
  do
    {
      char key[sizeof (int) * 3 + strlen (proto) + 2];
      char *result;
      size_t keylen, len;
      int int_len;

      /* key is: "port/proto" */
      keylen = snprintf (key, sizeof (key), "%d/%s", ntohs (port), proto);
      status = yperr2nss (yp_match (domain, "services.byname", key,
				    keylen, &result, &int_len));
      len = int_len;

      /* If we found the key, it's ok and parse the result. If not,
	 fall through and parse the complete table. */
      if (status == NSS_STATUS_SUCCESS)
	{
	  struct parser_data *pdata = (void *) buffer;
	  int parse_res;
	  char *p;

	  if ((size_t) (len + 1) > buflen)
	    {
	      free (result);
	      *errnop = ERANGE;
	      return NSS_STATUS_TRYAGAIN;
	    }

	  p = strncpy (buffer, result, len);
	  buffer[len] = '\0';
	  while (isspace (*p))
	    ++p;
	  free (result);
	  parse_res = _nss_files_parse_servent (p, serv, pdata,
						buflen, errnop);
	  if (parse_res < 0)
	    {
	      if (parse_res == -1)
		return NSS_STATUS_TRYAGAIN;
	      else
		return NSS_STATUS_NOTFOUND;
	    }
	  else
	    return NSS_STATUS_SUCCESS;
	}
    }
  while (protocol == NULL && (proto[0] == 't' ? (proto = "udp") : NULL));

  if (port == -1)
    return NSS_STATUS_NOTFOUND;

  struct ypall_callback ypcb;
  struct search_t req;

  ypcb.foreach = dosearch;
  ypcb.data = (char *) &req;
  req.name = NULL;
  req.proto = protocol;
  req.port = port;
  req.serv = serv;
  req.buffer = buffer;
  req.buflen = buflen;
  req.errnop = errnop;
  req.status = NSS_STATUS_NOTFOUND;
  status = yperr2nss (yp_all (domain, "services.byname", &ypcb));

  if (status != NSS_STATUS_SUCCESS)
    return status;

  return req.status;
}