/* Test of realloc function.
Copyright (C) 2010-2025 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <stdlib.h>
#include <errno.h>
#include <stdint.h>
#include "macros.h"
/* Work around clang bug
<https://github.com/llvm/llvm-project/issues/114772>. */
void *(*volatile my_realloc) (void *, size_t) = realloc;
#undef realloc
#define realloc my_realloc
int
main (int argc, _GL_UNUSED char **argv)
{
void *p;
/* Check that realloc (NULL, 0) is not a NULL pointer. */
p = realloc (NULL, 0);
ASSERT (p != NULL);
#ifdef NOT_YET
free (p);
/* Check that realloc (p, 0) for non-NULL p is not a NULL pointer. */
p = malloc (200);
p = realloc (p, 0);
ASSERT (p != NULL);
free (p);
/* Check that realloc (p, 0) for non-NULL p is not a NULL pointer. */
p = malloc (2 * 1024 * 1024);
p = realloc (p, 0);
ASSERT (p != NULL);
#endif
/* Check that realloc (p, n) fails when p is non-null and n exceeds
PTRDIFF_MAX. */
if (PTRDIFF_MAX < SIZE_MAX)
{
size_t one = argc != 12345;
void *r = realloc (p, PTRDIFF_MAX + one);
ASSERT (r == NULL);
/* Avoid a test failure due to glibc bug
<https://sourceware.org/PR27870>. */
if (!getenv ("MALLOC_CHECK_"))
ASSERT (errno == ENOMEM);
}
/* Check that realloc sets errno when it fails.
Do this only in 64-bit processes, because there are many bi-arch systems
nowadays where a 32-bit process can actually allocate 2 GiB of RAM. */
if (sizeof (size_t) >= 8)
{
void *r;
errno = 0;
r = realloc (p, SIZE_MAX / 10);
ASSERT (r == NULL);
ASSERT (errno == ENOMEM);
errno = 0;
r = realloc (p, SIZE_MAX / 3);
ASSERT (r == NULL);
ASSERT (errno == ENOMEM);
}
free (p);
return test_exit_status;
}
