1//===-- Unittests for mbtowc ---------------------------------------------===//
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/types/wchar_t.h"
10#include "src/__support/libc_errno.h"
11#include "src/wchar/mbtowc.h"
12#include "test/UnitTest/ErrnoCheckingTest.h"
13#include "test/UnitTest/Test.h"
14
15using LlvmLibcMBToWCTest = LIBC_NAMESPACE::testing::ErrnoCheckingTest;
16
17TEST_F(LlvmLibcMBToWCTest, OneByte) {
18 const char *ch = "A";
19 wchar_t dest[2];
20 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 1);
21 ASSERT_EQ(static_cast<char>(*dest), 'A');
22 ASSERT_EQ(n, 1);
23
24 // Should fail since we have not read enough
25 n = LIBC_NAMESPACE::mbtowc(dest, ch, 0);
26 ASSERT_EQ(n, -1);
27 ASSERT_ERRNO_EQ(EILSEQ);
28}
29
30TEST_F(LlvmLibcMBToWCTest, TwoByte) {
31 const char ch[2] = {static_cast<char>(0xC2),
32 static_cast<char>(0x8E)}; // Ž car symbol
33 wchar_t dest[2];
34 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 2);
35 ASSERT_EQ(static_cast<int>(*dest), 142);
36 ASSERT_EQ(n, 2);
37
38 // Should fail since we have not read enough
39 n = LIBC_NAMESPACE::mbtowc(dest, ch, 1);
40 ASSERT_EQ(n, -1);
41 // Should fail after trying to read next byte too
42 n = LIBC_NAMESPACE::mbtowc(dest, ch + 1, 1);
43 ASSERT_EQ(n, -1);
44 ASSERT_ERRNO_EQ(EILSEQ);
45}
46
47TEST_F(LlvmLibcMBToWCTest, ThreeByte) {
48 const char ch[3] = {static_cast<char>(0xE2), static_cast<char>(0x88),
49 static_cast<char>(0x91)}; // ∑ sigma symbol
50 wchar_t dest[2];
51 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 3);
52 ASSERT_EQ(static_cast<int>(*dest), 8721);
53 ASSERT_EQ(n, 3);
54
55 // Should fail since we have not read enough
56 n = LIBC_NAMESPACE::mbtowc(dest, ch, 2);
57 ASSERT_EQ(n, -1);
58 ASSERT_ERRNO_EQ(EILSEQ);
59}
60
61TEST_F(LlvmLibcMBToWCTest, FourByte) {
62 const char ch[4] = {static_cast<char>(0xF0), static_cast<char>(0x9F),
63 static_cast<char>(0xA4),
64 static_cast<char>(0xA1)}; // 🤡 clown emoji
65 wchar_t dest[2];
66 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 4);
67 ASSERT_EQ(static_cast<int>(*dest), 129313);
68 ASSERT_EQ(n, 4);
69
70 // Should fail since we have not read enough
71 n = LIBC_NAMESPACE::mbtowc(dest, ch, 2);
72 ASSERT_EQ(n, -1);
73 ASSERT_ERRNO_EQ(EILSEQ);
74}
75
76TEST_F(LlvmLibcMBToWCTest, InvalidByte) {
77 const char ch[1] = {static_cast<char>(0x80)};
78 wchar_t dest[2];
79 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 1);
80 ASSERT_EQ(n, -1);
81 ASSERT_ERRNO_EQ(EILSEQ);
82}
83
84TEST_F(LlvmLibcMBToWCTest, InvalidMultiByte) {
85 const char ch[4] = {static_cast<char>(0x80), static_cast<char>(0x00),
86 static_cast<char>(0x80),
87 static_cast<char>(0x00)}; // invalid sequence of bytes
88 wchar_t dest[2];
89 // Trying to push all 4 should error
90 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 4);
91 ASSERT_EQ(n, -1);
92 ASSERT_ERRNO_EQ(EILSEQ);
93
94 // Trying to push the second and third should correspond to null wc
95 n = LIBC_NAMESPACE::mbtowc(dest, ch + 1, 2);
96 ASSERT_EQ(n, 0);
97 ASSERT_TRUE(*dest == L'\0');
98}
99
100TEST_F(LlvmLibcMBToWCTest, InvalidLastByte) {
101 // Last byte is invalid since it does not have correct starting sequence.
102 // 0xC0 --> 11000000 starting sequence should be 10xxxxxx
103 const char ch[4] = {static_cast<char>(0xF1), static_cast<char>(0x80),
104 static_cast<char>(0x80), static_cast<char>(0xC0)};
105 wchar_t dest[2];
106 // Trying to push all 4 should error
107 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 4);
108 ASSERT_EQ(n, -1);
109 ASSERT_ERRNO_EQ(EILSEQ);
110}
111
112TEST_F(LlvmLibcMBToWCTest, ValidTwoByteWithExtraRead) {
113 const char ch[3] = {static_cast<char>(0xC2), static_cast<char>(0x8E),
114 static_cast<char>(0x80)};
115 wchar_t dest[2];
116 // Trying to push all 3 should return valid 2 byte
117 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 3);
118 ASSERT_EQ(n, 2);
119 ASSERT_EQ(static_cast<int>(*dest), 142);
120}
121
122TEST_F(LlvmLibcMBToWCTest, TwoValidTwoBytes) {
123 const char ch[4] = {static_cast<char>(0xC2), static_cast<char>(0x8E),
124 static_cast<char>(0xC7), static_cast<char>(0x8C)};
125 wchar_t dest[2];
126 int n = LIBC_NAMESPACE::mbtowc(dest, ch, 2);
127 ASSERT_EQ(n, 2);
128 ASSERT_EQ(static_cast<int>(*dest), 142);
129 n = LIBC_NAMESPACE::mbtowc(dest + 1, ch + 2, 2);
130 ASSERT_EQ(n, 2);
131 ASSERT_EQ(static_cast<int>(*(dest + 1)), 460);
132}
133
134TEST_F(LlvmLibcMBToWCTest, NullString) {
135 wchar_t dest[2] = {L'O', L'K'};
136 // reading on nullptr should return 0
137 int n = LIBC_NAMESPACE::mbtowc(dest, nullptr, 2);
138 ASSERT_EQ(n, 0);
139 ASSERT_TRUE(dest[0] == L'O');
140 // reading a null terminator should return 0
141 const char *ch = "\0";
142 n = LIBC_NAMESPACE::mbtowc(dest, ch, 1);
143 ASSERT_EQ(n, 0);
144}
145
146TEST_F(LlvmLibcMBToWCTest, NullWCPtr) {
147 const char ch[2] = {
148 static_cast<char>(0xC2),
149 static_cast<char>(0x8E),
150 };
151 // a null destination should still return the number of read bytes
152 int n = LIBC_NAMESPACE::mbtowc(nullptr, ch, 2);
153 ASSERT_EQ(n, 2);
154}
155

source code of libc/test/src/wchar/mbtowc_test.cpp