1 //===-- Unittests for memccpy ---------------------------------------------===//
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 "src/__support/CPP/ArrayRef.h"
10 #include "src/string/memccpy.h"
11 #include "utils/UnitTest/Test.h"
12 #include <stddef.h> // For size_t.
13 
14 class LlvmLibcMemccpyTest : public __llvm_libc::testing::Test {
15 public:
16   void check_memccpy(__llvm_libc::cpp::MutableArrayRef<char> dst,
17                      const __llvm_libc::cpp::ArrayRef<char> src, int end,
18                      size_t count,
19                      const __llvm_libc::cpp::ArrayRef<char> expected,
20                      size_t expectedCopied, bool shouldReturnNull = false) {
21     // Making sure we don't overflow buffer.
22     ASSERT_GE(dst.size(), count);
23     // Making sure memccpy returns dst.
24     void *result = __llvm_libc::memccpy(dst.data(), src.data(), end, count);
25 
26     if (shouldReturnNull) {
27       ASSERT_EQ(result, static_cast<void *>(nullptr));
28     } else {
29       ASSERT_EQ(result, static_cast<void *>(dst.data() + expectedCopied));
30     }
31 
32     // Expected must be of the same size as dst.
33     ASSERT_EQ(dst.size(), expected.size());
34     // Expected and dst are the same.
35     for (size_t i = 0; i < expected.size(); ++i)
36       ASSERT_EQ(expected[i], dst[i]);
37   }
38 };
39 
40 TEST_F(LlvmLibcMemccpyTest, UntouchedUnrelatedEnd) {
41   char dst[] = {'a', 'b'};
42   const char src[] = {'x', '\0'};
43   const char expected[] = {'a', 'b'};
44   check_memccpy(dst, src, 'z', 0, expected, 0, true);
45 }
46 
47 TEST_F(LlvmLibcMemccpyTest, UntouchedStartsWithEnd) {
48   char dst[] = {'a', 'b'};
49   const char src[] = {'x', '\0'};
50   const char expected[] = {'a', 'b'};
51   check_memccpy(dst, src, 'x', 0, expected, 0, true);
52 }
53 
54 TEST_F(LlvmLibcMemccpyTest, CopyOneUnrelatedEnd) {
55   char dst[] = {'a', 'b'};
56   const char src[] = {'x', 'y'};
57   const char expected[] = {'x', 'b'};
58   check_memccpy(dst, src, 'z', 1, expected, 1, true);
59 }
60 
61 TEST_F(LlvmLibcMemccpyTest, CopyOneStartsWithEnd) {
62   char dst[] = {'a', 'b'};
63   const char src[] = {'x', 'y'};
64   const char expected[] = {'x', 'b'};
65   check_memccpy(dst, src, 'x', 1, expected, 1);
66 }
67 
68 TEST_F(LlvmLibcMemccpyTest, CopyTwoUnrelatedEnd) {
69   char dst[] = {'a', 'b'};
70   const char src[] = {'x', 'y'};
71   const char expected[] = {'x', 'y'};
72   check_memccpy(dst, src, 'z', 2, expected, 2, true);
73 }
74 
75 TEST_F(LlvmLibcMemccpyTest, CopyTwoStartsWithEnd) {
76   char dst[] = {'a', 'b'};
77   const char src[] = {'x', 'y'};
78   const char expected[] = {'x', 'b'};
79   check_memccpy(dst, src, 'x', 2, expected, 1);
80 }
81