libc/test/src/string/memccpy_test.cpp

   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/span.h"
  10 #include "src/string/memccpy.h"
  11 #include "test/UnitTest/Test.h"
  12 #include <stddef.h> // For size_t.
  13
  14 class LlvmLibcMemccpyTest : public LIBC_NAMESPACE::testing::Test {
  15 public:
  16   void check_memccpy(LIBC_NAMESPACE::cpp::span<char> dst,
  17                      const LIBC_NAMESPACE::cpp::span<const char> src, int end,
  18                      size_t count,
  19                      const LIBC_NAMESPACE::cpp::span<const 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 = LIBC_NAMESPACE::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 }