1//===-- Unittests for memcpy ----------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "hdr/signal_macros.h"
10#include "memory_utils/memory_check_utils.h"
11#include "src/__support/macros/config.h"
12#include "src/__support/macros/properties/os.h" // LIBC_TARGET_OS_IS_LINUX
13#include "src/string/memcpy.h"
14#include "test/UnitTest/Test.h"
15
16#if !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
17#include "memory_utils/protected_pages.h"
18#endif // !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
19
20namespace LIBC_NAMESPACE_DECL {
21
22// Adapt CheckMemcpy signature to memcpy.
23static inline void Adaptor(cpp::span<char> dst, cpp::span<char> src,
24 size_t size) {
25 LIBC_NAMESPACE::memcpy(dst.begin(), src.begin(), size);
26}
27
28TEST(LlvmLibcMemcpyTest, SizeSweep) {
29 static constexpr size_t kMaxSize = 400;
30 Buffer SrcBuffer(kMaxSize);
31 Buffer DstBuffer(kMaxSize);
32 Randomize(SrcBuffer.span());
33 for (size_t size = 0; size < kMaxSize; ++size) {
34 auto src = SrcBuffer.span().subspan(0, size);
35 auto dst = DstBuffer.span().subspan(0, size);
36 ASSERT_TRUE(CheckMemcpy<Adaptor>(dst, src, size));
37 }
38}
39
40#if !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
41
42TEST(LlvmLibcMemcpyTest, CheckAccess) {
43 static constexpr size_t MAX_SIZE = 1024;
44 LIBC_ASSERT(MAX_SIZE < GetPageSize());
45 ProtectedPages pages;
46 const Page write_buffer = pages.GetPageA().WithAccess(PROT_WRITE);
47 const Page read_buffer = [&]() {
48 // We fetch page B in write mode.
49 auto page = pages.GetPageB().WithAccess(PROT_WRITE);
50 // And fill it with random numbers.
51 for (size_t i = 0; i < page.page_size; ++i)
52 page.page_ptr[i] = static_cast<uint8_t>(rand());
53 // Then return it in read mode.
54 return page.WithAccess(PROT_READ);
55 }();
56 for (size_t size = 0; size < MAX_SIZE; ++size) {
57 // We cross-check the function with two sources and two destinations.
58 // - The first of them (bottom) is always page aligned and faults when
59 // accessing bytes before it.
60 // - The second one (top) is not necessarily aligned and faults when
61 // accessing bytes after it.
62 const uint8_t *sources[2] = {read_buffer.bottom(size),
63 read_buffer.top(size)};
64 uint8_t *destinations[2] = {write_buffer.bottom(size),
65 write_buffer.top(size)};
66 for (const uint8_t *src : sources) {
67 for (uint8_t *dst : destinations) {
68 LIBC_NAMESPACE::memcpy(dst, src, size);
69 }
70 }
71 }
72}
73
74#endif // !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
75
76#if defined(LIBC_ADD_NULL_CHECKS) && !defined(LIBC_HAS_SANITIZER)
77
78TEST(LlvmLibcMemcpyTest, CrashOnNullPtr) {
79 ASSERT_DEATH([]() { LIBC_NAMESPACE::memcpy(nullptr, nullptr, 1); },
80 WITH_SIGNAL(-1));
81}
82#endif // defined(LIBC_ADD_NULL_CHECKS) && !defined(LIBC_HAS_SANITIZER)
83
84} // namespace LIBC_NAMESPACE_DECL
85

source code of libc/test/src/string/memcpy_test.cpp