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/*
* Copyright (C) 2008-2024 Free Software Foundation, Inc.
* Written by Eric Blake and Bruno Haible
*
* 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>
#include <string.h>
#include "signature.h"
SIGNATURE_CHECK (memrchr, void *, (void const *, int, size_t));
#include <stdlib.h>
#include "zerosize-ptr.h"
#include "macros.h"
/* Work around GCC bug 101494. */
#if _GL_GNUC_PREREQ (4, 7) && __GNUC__ < 12
# pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
#endif
/* Calculating void * + int is not portable, so this wrapper converts
to char * to make the tests easier to write. */
#define MEMRCHR (char *) memrchr
int
main (void)
{
size_t n = 0x100000;
char *input = malloc (n);
ASSERT (input);
input[n - 1] = 'a';
input[n - 2] = 'b';
memset (input + n - 1026, 'c', 1024);
memset (input + 2, 'd', n - 1028);
input[1] = 'e';
input[0] = 'a';
/* Basic behavior tests. */
ASSERT (MEMRCHR (input, 'a', n) == input + n - 1);
ASSERT (MEMRCHR (input, 'a', 0) == NULL);
void *page_boundary = zerosize_ptr ();
if (page_boundary)
ASSERT (MEMRCHR (page_boundary, 'a', 0) == NULL);
ASSERT (MEMRCHR (input, 'b', n) == input + n - 2);
ASSERT (MEMRCHR (input, 'c', n) == input + n - 3);
ASSERT (MEMRCHR (input, 'd', n) == input + n - 1027);
ASSERT (MEMRCHR (input, 'a', n - 1) == input);
ASSERT (MEMRCHR (input, 'e', n - 1) == input + 1);
ASSERT (MEMRCHR (input, 'f', n) == NULL);
ASSERT (MEMRCHR (input, '\0', n) == NULL);
/* Check that a very long haystack is handled quickly if the byte is
found near the end. */
{
size_t repeat = 10000;
for (; repeat > 0; repeat--)
{
ASSERT (MEMRCHR (input, 'c', n) == input + n - 3);
}
}
/* Alignment tests. */
{
int i, j;
for (i = 0; i < 32; i++)
{
for (j = 0; j < 256; j++)
input[i + j] = j;
for (j = 0; j < 256; j++)
{
ASSERT (MEMRCHR (input + i, j, 256) == input + i + j);
}
}
}
free (input);
return test_exit_status;
}
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