Files
test/intern/guardedalloc/intern/mallocn_inline.hh

90 lines
2.7 KiB
C++

/* SPDX-FileCopyrightText: 2002-2017 `Jason Evans <jasone@canonware.com>`. All rights reserved.
* SPDX-FileCopyrightText: 2007-2012 Mozilla Foundation. All rights reserved.
* SPDX-FileCopyrightText: 2009-2017 Facebook, Inc. All rights reserved.
*
* SPDX-License-Identifier: BSD-2-Clause */
#pragma once
/** \file
* \ingroup intern_mem
*/
#include <cstdlib>
/* BEGIN copied from BLI_asan.h */
/* Clang defines this. */
#ifndef __has_feature
# define __has_feature(x) 0
#endif
#if (defined(__SANITIZE_ADDRESS__) || __has_feature(address_sanitizer)) && \
(!defined(_MSC_VER) || _MSC_VER > 1929) /* MSVC 2019 and below doesn't ship ASAN headers. */
# include "sanitizer/asan_interface.h"
# define WITH_ASAN
#else
/* Ensure return value is used. Just using UNUSED_VARS results in a warning. */
# define ASAN_POISON_MEMORY_REGION(addr, size) (void)(0 && ((size) != 0 && (addr) != NULL))
# define ASAN_UNPOISON_MEMORY_REGION(addr, size) (void)(0 && ((size) != 0 && (addr) != NULL))
#endif
/* END copied from BLI_asan.h */
MEM_INLINE bool MEM_size_safe_multiply(size_t a, size_t b, size_t *result)
{
/* A size_t with its high-half bits all set to 1. */
const size_t high_bits = SIZE_MAX << (sizeof(size_t) * 8 / 2);
*result = a * b;
if (UNLIKELY(*result == 0)) {
return (a == 0 || b == 0);
}
/*
* We got a non-zero size, but we don't know if we overflowed to get
* there. To avoid having to do a divide, we'll be clever and note that
* if both A and B can be represented in N/2 bits, then their product
* can be represented in N bits (without the possibility of overflow).
*/
return ((high_bits & (a | b)) == 0 || (*result / b == a));
}
/**
* Util to trigger an error for the given memory block.
*
* When ASAN is available, it will poison the memory block before accessing it, to trigger a
* detailed ASAN report. Otherwise, it will abort if aborting on assert is set.
*/
#ifdef WITH_ASAN
MEM_INLINE void MEM_trigger_error_on_memory_block(const void *address, const size_t size)
{
if (address == nullptr) {
# ifdef WITH_ASSERT_ABORT
abort();
# endif
return;
}
/* Trigger ASAN error by poisoning the memory and accessing it. */
ASAN_POISON_MEMORY_REGION(address, size);
char *buffer = const_cast<char *>(static_cast<const char *>(address));
const char c = *buffer;
*buffer &= 255;
*buffer = c;
/* In case ASAN is set to not terminate on error, but abort on assert is requested. */
# ifdef WITH_ASSERT_ABORT
abort();
# endif
ASAN_UNPOISON_MEMORY_REGION(address, size);
}
#else
MEM_INLINE void MEM_trigger_error_on_memory_block(const void * /*address*/,
const size_t /*size*/)
{
# ifdef WITH_ASSERT_ABORT
abort();
# endif
}
#endif