1// Copyright (C) 2011 The Libphonenumber Authors
2//
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#ifndef I18N_PHONENUMBERS_ENCODING_UTILS_H_
16#define I18N_PHONENUMBERS_ENCODING_UTILS_H_
17
18#include "phonenumbers/base/basictypes.h"
19#include "phonenumbers/utf/unilib.h"
20#include "phonenumbers/utf/utf.h"
21
22namespace i18n {
23namespace phonenumbers {
24
25class EncodingUtils {
26 public:
27  // Decodes one Unicode code-point value from a UTF-8 array. Returns the number
28  // of bytes read from the array. If the array does not contain valid UTF-8,
29  // the function stores 0xFFFD in the output variable and returns 1.
30  static inline int DecodeUTF8Char(const char* in, char32* out) {
31    Rune r;
32    int len = chartorune(&r, in);
33    *out = r;
34    return len;
35  }
36
37  static const char* AdvanceOneUTF8Character(const char* buf_utf8) {
38      return buf_utf8 + UniLib::OneCharLen(buf_utf8);
39  }
40
41  static const char* BackUpOneUTF8Character(const char* start,
42                                            const char* end) {
43    while (start < end && UniLib::IsTrailByte(*--end)) {}
44    return end;
45  }
46};
47
48}  // namespace phonenumbers
49}  // namespace i18n
50
51#endif  // I18N_PHONENUMBERS_ENCODING_UTILS_H_
52