1  /* Copyright (C) 2000-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <stdlib.h>
      20  #include <netdb.h>
      21  #include "nsswitch.h"
      22  
      23  void *
      24  __nss_getent (getent_r_function func, void **resbuf, char **buffer,
      25  	      size_t buflen, size_t *buffer_size, int *h_errnop)
      26  {
      27    void *result;
      28  
      29    if (*buffer == NULL)
      30      {
      31        *buffer_size = buflen;
      32        *buffer = malloc (*buffer_size);
      33      }
      34  
      35    while (*buffer != NULL
      36  	 && func (resbuf, *buffer, *buffer_size, &result, h_errnop) == ERANGE
      37  	 && (h_errnop == NULL || *h_errnop == NETDB_INTERNAL))
      38      {
      39        char *new_buf;
      40        *buffer_size *= 2;
      41        new_buf = realloc (*buffer, *buffer_size);
      42        if (new_buf == NULL)
      43  	{
      44  	  /* We are out of memory.  Free the current buffer so that the
      45  	     process gets a chance for a normal termination.  */
      46  	  int save = errno;
      47  	  free (*buffer);
      48  	  __set_errno (save);
      49  	}
      50        *buffer = new_buf;
      51      }
      52  
      53    if (*buffer == NULL)
      54      result = NULL;
      55  
      56    return result;
      57  }