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/* Copyright (C) 1999, 2000 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 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 <assert.h>
#include <errno.h>
#include <netdb.h>
#include <stdlib.h>
#include "nsswitch.h"
/* We avoid using a too large buffer in case the user is accumulating the
results and there is lots of unused space in the allocated buffer. */
#define BUFLEN 512
struct hostent *
getipnodebyaddr (const void *addr, socklen_t len, int type, int *error_num)
{
size_t buffer_size;
char *buffer;
struct hostent *result;
buffer_size = BUFLEN;
buffer = malloc (buffer_size);
while (buffer != NULL
&& __gethostbyaddr_r (addr, len, type, (struct hostent *) buffer,
(char *) ((struct hostent *) buffer + 1),
buffer_size - sizeof (struct hostent),
&result, error_num) == ERANGE
&& *error_num == NETDB_INTERNAL)
{
buffer_size += BUFLEN;
buffer = realloc (buffer, buffer_size);
if (buffer == NULL)
{
*error_num = TRY_AGAIN;
assert (result == NULL);
return NULL;
}
}
return buffer == NULL ? NULL : result;
}
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