1 /*
2  * Copyright (c) 2024 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef COMMON_UTILS_H
17 #define COMMON_UTILS_H
18 
19 #include <codecvt>
20 #include <locale>
21 #include <memory.h>
22 #include <securec.h>
23 #include <string.h>
24 
25 namespace OHOS {
26 namespace Rosen {
27 namespace Drawing {
28 const uint16_t LOW_BYTE_MASK = 0x00FF;
29 const uint16_t HIGH_BYTE_MASK = 0xFF00;
30 const int BYTE_SHIFT = 8;
31 
IsUtf8(const char* text, uint32_t len)32 [[maybe_unused]] static bool IsUtf8(const char* text, uint32_t len)
33 {
34     uint32_t n = 0;
35     for (uint32_t i = 0; i < len; i++) {
36         uint32_t c = text[i];
37         if (c <= 0x7F) { // 0x00 and 0x7F is the range of utf-8
38             n = 0;
39         } else if ((c & 0xE0) == 0xC0) { // 0xE0 and 0xC0 is the range of utf-8
40             n = 1;
41         } else if (c == 0xED && i < (len - 1) && (text[i + 1] & 0xA0) == 0xA0) { // 0xA0 and 0xED is the range of utf-8
42             return false;
43         } else if ((c & 0xF0) == 0xE0) { // 0xE0 and 0xF0 is the range of utf-8
44             n = 2;                       // 2 means the size of range
45         } else if ((c & 0xF8) == 0xF0) { // 0xF0 and 0xF8 is the range of utf-8
46             n = 3;                       // 3 means the size of range
47         } else {
48             return false;
49         }
50         for (uint32_t j = 0; j < n && i < len; j++) {
51             // 0x80 and 0xC0 is the range of utf-8
52             i++;
53             if ((i == len) || ((text[i] & 0xC0) != 0x80)) {
54                 return false;
55             }
56         }
57     }
58     return true;
59 }
60 
IsBigEndian()61 [[maybe_unused]] static inline bool IsBigEndian()
62 {
63     int num = 1;
64     return (*(reinterpret_cast<uint8_t*>(&num)) == 0);
65 }
66 
ConvertToString(const uint8_t* data, size_t len, std::string& fullNameString)67 [[maybe_unused]] static bool ConvertToString(const uint8_t* data, size_t len, std::string& fullNameString)
68 {
69     if (data == nullptr || len == 0) {
70         return false;
71     }
72 
73     size_t utf16Len = len / sizeof(char16_t);
74     std::unique_ptr<char16_t[]> utf16Str = std::make_unique<char16_t[]>(utf16Len);
75 
76     if (IsBigEndian()) {
77         errno_t ret = memcpy_s(utf16Str.get(), utf16Len * sizeof(char16_t), data, len);
78         if (ret != EOK) {
79             return false;
80         }
81     } else {
82         for (size_t i = 0; i < utf16Len; ++i) {
83             const char16_t* utf16Data = reinterpret_cast<const char16_t*>(data);
84             uint16_t temp = static_cast<uint16_t>(utf16Data[i]);
85             utf16Str[i] = static_cast<char16_t>((temp & LOW_BYTE_MASK) << BYTE_SHIFT |
86                 (temp & HIGH_BYTE_MASK) >> BYTE_SHIFT);
87         }
88     }
89 
90     std::u16string utf16String(utf16Str.get(), utf16Len);
91     std::wstring_convert<std::codecvt_utf8_utf16<char16_t>, char16_t> converter;
92     fullNameString = converter.to_bytes(utf16String);
93 
94     return true;
95 }
96 }
97 }
98 }
99 #endif