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/* Copyright (C) 1996-2001,2003, 2004 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   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 <assert.h>

#include <errno.h>

#define _IO_MTSAFE_IO

#include <bits/libc-lock.h>

#include <stdlib.h>

#include <resolv.h>

#include "nsswitch.h"

/*******************************************************************\

|* Here we assume several symbols to be defined:                   *|

|*                                                                 *|

|* LOOKUP_TYPE   - the return type of the function                 *|

|*                                                                 *|

|* FUNCTION_NAME - name of the non-reentrant function              *|

|*                                                                 *|

|* DATABASE_NAME - name of the database the function accesses      *|

|*                 (e.g., host, services, ...)                     *|

|*                                                                 *|

|* ADD_PARAMS    - additional parameter, can vary in number        *|

|*                                                                 *|

|* ADD_VARIABLES - names of additional parameter                   *|

|*                                                                 *|

|* BUFLEN        - length of buffer allocated for the non          *|

|*                 reentrant version                               *|

|*                                                                 *|

|* Optionally the following vars can be defined:                   *|

|*                                                                 *|

|* NEED_H_ERRNO  - an extra parameter will be passed to point to   *|

|*                 the global `h_errno' variable.                  *|

|*                                                                 *|

\*******************************************************************/

/* To make the real sources a bit prettier.  */

#define REENTRANT_NAME APPEND_R (FUNCTION_NAME)

#define APPEND_R(name) APPEND_R1 (name)

#define APPEND_R1(name) name##_r

#define INTERNAL(name) INTERNAL1 (name)

#define INTERNAL1(name) __##name

/* Sometimes we need to store error codes in the `h_errno' variable.  */

#ifdef NEED_H_ERRNO

# define H_ERRNO_PARM , int *h_errnop

# define H_ERRNO_VAR , &h_errno_tmp

# define H_ERRNO_VAR_P &h_errno_tmp

#else

# define H_ERRNO_PARM

# define H_ERRNO_VAR

# define H_ERRNO_VAR_P NULL

#endif

#ifdef HAVE_AF

# define AF_VAL af

#else

# define AF_VAL AF_INET

#endif

/* Prototype for reentrant version we use here.  */

extern int INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf,

                                      char *buffer, size_t buflen,

                                      LOOKUP_TYPE **result H_ERRNO_PARM);

/* We need to protect the dynamic buffer handling.  */

__libc_lock_define_initialized (static, lock);

/* This points to the static buffer used.  */

libc_freeres_ptr (static char *buffer);

LOOKUP_TYPE *

FUNCTION_NAME (ADD_PARAMS)

{

  static size_t buffer_size;

  static LOOKUP_TYPE resbuf;

  LOOKUP_TYPE *result;

#ifdef NEED_H_ERRNO

  int h_errno_tmp = 0;

#endif

  /* Get lock.  */

  __libc_lock_lock (lock);

  if (buffer == NULL)

    {

      buffer_size = BUFLEN;

      buffer = (char *) malloc (buffer_size);

    }

#ifdef HANDLE_DIGITS_DOTS

  if (buffer != NULL)

    {

      if (__nss_hostname_digits_dots (name, &resbuf, &buffer,

                                      &buffer_size, 0, &result, NULL, AF_VAL,

                                      H_ERRNO_VAR_P))

        goto done;

    }

#endif

  while (buffer != NULL

         && (INTERNAL (REENTRANT_NAME) (ADD_VARIABLES, &resbuf, buffer,

                                        buffer_size, &result H_ERRNO_VAR)

             == ERANGE)

#ifdef NEED_H_ERRNO

         && h_errno_tmp == NETDB_INTERNAL

#endif

         )

    {

      char *new_buf;

      buffer_size *= 2;

      new_buf = (char *) realloc (buffer, buffer_size);

      if (new_buf == NULL)

        {

          /* We are out of memory.  Free the current buffer so that the

             process gets a chance for a normal termination.  */

          free (buffer);

          errno = (ENOMEM);

        }

      buffer = new_buf;

    }

  if (buffer == NULL)

    result = NULL;

#ifdef HANDLE_DIGITS_DOTS

done:

#endif

  /* Release lock.  */

  __libc_lock_unlock (lock);

#ifdef NEED_H_ERRNO

  if (h_errno_tmp != 0)

    h_errno = (h_errno_tmp);

#endif

  return result;

}

static_link_warning (FUNCTION_NAME)