Open Chinese Convert: UTF8Util.hpp Source File

Open Chinese Convert 1.0.6 A project for conversion between Traditional and Simplified Chinese

UTF8Util.hpp
1 /*
2 * Open Chinese Convert
3 *
4 * Copyright 2013 BYVoid <byvoid@byvoid.com>
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19 #pragma once
20
21 #ifdef _MSC_VER
22 #define NOMINMAX
23 #include <Windows.h>
24 #undef NOMINMAX
25 #endif // _MSC_VER
26
27 #include "Common.hpp"
28
29 namespace opencc {
34 class OPENCC_EXPORT UTF8Util {
35 public:
39 static void SkipUtf8Bom(FILE* fp);
40
45 static size_t NextCharLengthNoException(const char* str) {
46 char ch = *str;
47 if ((ch & 0xF0) == 0xE0) {
48 return 3;
49 } else if ((ch & 0x80) == 0x00) {
50 return 1;
51 } else if ((ch & 0xE0) == 0xC0) {
52 return 2;
53 } else if ((ch & 0xF8) == 0xF0) {
54 return 4;
55 } else if ((ch & 0xFC) == 0xF8) {
56 return 5;
57 } else if ((ch & 0xFE) == 0xFC) {
58 return 6;
59 }
60 return 0;
61 }
62
66 static size_t NextCharLength(const char* str) {
67 size_t length = NextCharLengthNoException(str);
68 if (length == 0) {
69 throw InvalidUTF8(str);
70 }
71 return length;
72 }
73
77 static size_t PrevCharLength(const char* str) {
78 {
79 const size_t length = NextCharLengthNoException(str - 3);
80 if (length == 3) {
81 return length;
82 }
83 }
84 {
85 const size_t length = NextCharLengthNoException(str - 1);
86 if (length == 1) {
87 return length;
88 }
89 }
90 {
91 const size_t length = NextCharLengthNoException(str - 2);
92 if (length == 2) {
93 return length;
94 }
95 }
96 for (size_t i = 4; i <= 6; i++) {
97 const size_t length = NextCharLengthNoException(str - i);
98 if (length == i) {
99 return length;
100 }
101 }
102 throw InvalidUTF8(str);
103 }
104
108 static const char* NextChar(const char* str) {
109 return str + NextCharLength(str);
110 }
111
115 static const char* PrevChar(const char* str) {
116 return str - PrevCharLength(str);
117 }
118
122 static size_t Length(const char* str) {
123 size_t length = 0;
124 while (*str != '\0') {
125 str = NextChar(str);
126 length++;
127 }
128 return length;
129 }
130
137 static const char* FindNextInline(const char* str, const char ch) {
138 while (!IsLineEndingOrFileEnding(*str) && *str != ch) {
139 str = NextChar(str);
140 }
141 return str;
142 }
143
147 static bool IsLineEndingOrFileEnding(const char ch) {
148 return ch == '\0' || ch == '\n' || ch == '\r';
149 }
150
154 static string FromSubstr(const char* str, size_t length) {
155 string newStr;
156 newStr.resize(length);
157 strncpy(const_cast<char*>(newStr.c_str()), str, length);
158 return newStr;
159 }
160
164 static bool NotShorterThan(const char* str, size_t byteLength) {
165 while (byteLength > 0) {
166 if (*str == '\0') {
167 return false;
168 }
169 byteLength--;
170 str++;
171 }
172 return true;
173 }
174
179 static string TruncateUTF8(const char* str, size_t maxByteLength) {
180 string wordTrunc;
181 if (NotShorterThan(str, maxByteLength)) {
182 size_t len = 0;
183 const char* pStr = str;
184 for (;;) {
185 const size_t charLength = NextCharLength(pStr);
186 if (len + charLength > maxByteLength) {
187 break;
188 }
189 pStr += charLength;
190 len += charLength;
191 }
192 wordTrunc = FromSubstr(str, len);
193 } else {
194 wordTrunc = str;
195 }
196 return wordTrunc;
197 }
198
202 static void ReplaceAll(string& str, const char* from, const char* to) {
203 string::size_type pos = 0;
204 string::size_type fromLen = strlen(from);
205 string::size_type toLen = strlen(to);
206 while ((pos = str.find(from, pos)) != string::npos) {
207 str.replace(pos, fromLen, to);
208 pos += toLen;
209 }
210 }
211
215 static string Join(const vector<string>& strings, const string& separator) {
216 std::ostringstream buffer;
217 bool first = true;
218 for (const auto& str : strings) {
219 if (!first) {
220 buffer << separator;
221 }
222 buffer << str;
223 first = false;
224 }
225 return buffer.str();
226 }
227
231 static string Join(const vector<string>& strings) {
232 std::ostringstream buffer;
233 for (const auto& str : strings) {
234 buffer << str;
235 }
236 return buffer.str();
237 }
238
239 static void GetByteMap(const char* str, const size_t utf8Length,
240 vector<size_t>* byteMap) {
241 if (byteMap->size() < utf8Length) {
242 byteMap->resize(utf8Length);
243 }
244 const char* pstr = str;
245 for (size_t i = 0; i < utf8Length; i++) {
246 (*byteMap)[i] = pstr - str;
247 pstr = NextChar(pstr);
248 }
249 }
250
251 #ifdef _MSC_VER
252 static std::wstring GetPlatformString(const std::string& str) {
253 return U8ToU16(str);
254 }
255 #else
256 static std::string GetPlatformString(const std::string& str) {
257 return str;
258 }
259 #endif // _MSC_VER
260
261
262 #ifdef _MSC_VER
263 static std::string U16ToU8(const std::wstring& wstr) {
264 std::string ret;
265 int length = static_cast<int>(wstr.length());
266 int convcnt = WideCharToMultiByte(CP_UTF8, 0, wstr.c_str(), length, NULL, 0, NULL, NULL);
267 if (convcnt > 0) {
268 ret.resize(convcnt);
269 WideCharToMultiByte(CP_UTF8, 0, wstr.c_str(), length, &ret[0], convcnt, NULL, NULL);
270 }
271 return ret;
272 }
273
274 static std::wstring U8ToU16(const std::string& str) {
275 std::wstring ret;
276 int length = static_cast<int>(str.length());
277 int convcnt = MultiByteToWideChar(CP_UTF8, 0, str.c_str(), length, NULL, 0);
278 if (convcnt > 0) {
279 ret.resize(convcnt);
280 MultiByteToWideChar(CP_UTF8, 0, str.c_str(), length, &ret[0], convcnt);
281 }
282 return ret;
283 }
284 #endif // _MSC_VER
285 };
286 }
opencc::UTF8Util::Length
static size_t Length(const char *str)
Returns the UTF8 length of a valid UTF8 string.
Definition: UTF8Util.hpp:122
opencc::UTF8Util::FindNextInline
static const char * FindNextInline(const char *str, const char ch)
Finds a character in the same line.
Definition: UTF8Util.hpp:137
opencc::UTF8Util::NextCharLengthNoException
static size_t NextCharLengthNoException(const char *str)
Returns the length in byte for the next UTF8 character.
Definition: UTF8Util.hpp:45
opencc::UTF8Util::Join
static string Join(const vector< string > &strings)
Joins a string vector in to a string.
Definition: UTF8Util.hpp:231
opencc::UTF8Util::NotShorterThan
static bool NotShorterThan(const char *str, size_t byteLength)
Returns true if the given string is longer or as long as the given length.
Definition: UTF8Util.hpp:164
opencc::UTF8Util::Join
static string Join(const vector< string > &strings, const string &separator)
Joins a string vector in to a string with a separator.
Definition: UTF8Util.hpp:215
opencc::UTF8Util
UTF8 string utilities.
Definition: UTF8Util.hpp:34
opencc::UTF8Util::NextCharLength
static size_t NextCharLength(const char *str)
Returns the length in byte for the next UTF8 character.
Definition: UTF8Util.hpp:66
opencc::InvalidUTF8
Definition: Exception.hpp:76
opencc::UTF8Util::TruncateUTF8
static string TruncateUTF8(const char *str, size_t maxByteLength)
Truncates a string with a maximal length in byte.
Definition: UTF8Util.hpp:179
opencc::UTF8Util::IsLineEndingOrFileEnding
static bool IsLineEndingOrFileEnding(const char ch)
Returns ture if the character is a line ending or end of file.
Definition: UTF8Util.hpp:147
opencc::UTF8Util::FromSubstr
static string FromSubstr(const char *str, size_t length)
Copies a substring with given length to a new std::string.
Definition: UTF8Util.hpp:154
opencc::UTF8Util::ReplaceAll
static void ReplaceAll(string &str, const char *from, const char *to)
Replaces all patterns in a string in place.
Definition: UTF8Util.hpp:202
opencc::UTF8Util::PrevCharLength
static size_t PrevCharLength(const char *str)
Returns the length in byte for the previous UTF8 character.
Definition: UTF8Util.hpp:77
opencc::UTF8Util::PrevChar
static const char * PrevChar(const char *str)
Move the char* pointer before the previous UTF8 character.
Definition: UTF8Util.hpp:115
opencc::UTF8Util::NextChar
static const char * NextChar(const char *str)
Returns the char* pointer over the next UTF8 character.
Definition: UTF8Util.hpp:108