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/*
* Copyright (c) 2015-2021 Dmitry V. Levin <ldv@strace.io>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include <string.h>
#include <sys/mman.h>
void *
tail_alloc(const size_t size)
{
const size_t page_size = get_page_size();
const size_t len = (size + page_size - 1) & -page_size;
const size_t alloc_size = len + 6 * page_size;
void *p = mmap(NULL, alloc_size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (MAP_FAILED == p)
perror_msg_and_fail("mmap(%zu)", alloc_size);
void *start_work = p + 3 * page_size;
void *tail_guard = start_work + len;
if (munmap(p, page_size) ||
munmap(p + 2 * page_size, page_size) ||
munmap(tail_guard, page_size) ||
munmap(tail_guard + 2 * page_size, page_size))
perror_msg_and_fail("munmap");
memset(start_work, 0xff, len);
return tail_guard - size;
}
void *
tail_memdup(const void *p, const size_t size)
{
void *dest = tail_alloc(size);
memcpy(dest, p, size);
return dest;
}
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