1/* realloc() function that is glibc compatible.
2
3   Copyright (C) 1997, 2003-2004, 2006-2007, 2009-2022 Free Software
4   Foundation, Inc.
5
6   This file is free software: you can redistribute it and/or modify
7   it under the terms of the GNU Lesser General Public License as
8   published by the Free Software Foundation; either version 2.1 of the
9   License, or (at your option) any later version.
10
11   This file is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14   GNU Lesser General Public License for more details.
15
16   You should have received a copy of the GNU Lesser General Public License
17   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
18
19/* written by Jim Meyering and Bruno Haible */
20
21#include <config.h>
22
23#include <stdlib.h>
24
25#include <errno.h>
26
27#include "xalloc-oversized.h"
28
29/* Call the system's realloc below.  This file does not define
30   _GL_USE_STDLIB_ALLOC because it needs Gnulib's malloc if present.  */
31#undef realloc
32
33/* Change the size of an allocated block of memory P to N bytes,
34   with error checking.  If P is NULL, use malloc.  Otherwise if N is zero,
35   free P and return NULL.  */
36
37void *
38rpl_realloc (void *p, size_t n)
39{
40  if (p == NULL)
41    return malloc (n);
42
43  if (n == 0)
44    {
45      free (p);
46      return NULL;
47    }
48
49  if (xalloc_oversized (n, 1))
50    {
51      errno = ENOMEM;
52      return NULL;
53    }
54
55  void *result = realloc (p, n);
56
57#if !HAVE_MALLOC_POSIX
58  if (result == NULL)
59    errno = ENOMEM;
60#endif
61
62  return result;
63}
64