| 1 | // Copyright 2017 The Abseil 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 | //      https://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 | // UTF8 utilities, implemented to reduce dependencies. | 
|---|
| 16 |  | 
|---|
| 17 | #include "absl/strings/internal/utf8.h" | 
|---|
| 18 |  | 
|---|
| 19 | namespace absl { | 
|---|
| 20 | namespace strings_internal { | 
|---|
| 21 |  | 
|---|
| 22 | size_t EncodeUTF8Char(char *buffer, char32_t utf8_char) { | 
|---|
| 23 | if (utf8_char <= 0x7F) { | 
|---|
| 24 | *buffer = static_cast<char>(utf8_char); | 
|---|
| 25 | return 1; | 
|---|
| 26 | } else if (utf8_char <= 0x7FF) { | 
|---|
| 27 | buffer[1] = 0x80 | (utf8_char & 0x3F); | 
|---|
| 28 | utf8_char >>= 6; | 
|---|
| 29 | buffer[0] = 0xC0 | utf8_char; | 
|---|
| 30 | return 2; | 
|---|
| 31 | } else if (utf8_char <= 0xFFFF) { | 
|---|
| 32 | buffer[2] = 0x80 | (utf8_char & 0x3F); | 
|---|
| 33 | utf8_char >>= 6; | 
|---|
| 34 | buffer[1] = 0x80 | (utf8_char & 0x3F); | 
|---|
| 35 | utf8_char >>= 6; | 
|---|
| 36 | buffer[0] = 0xE0 | utf8_char; | 
|---|
| 37 | return 3; | 
|---|
| 38 | } else { | 
|---|
| 39 | buffer[3] = 0x80 | (utf8_char & 0x3F); | 
|---|
| 40 | utf8_char >>= 6; | 
|---|
| 41 | buffer[2] = 0x80 | (utf8_char & 0x3F); | 
|---|
| 42 | utf8_char >>= 6; | 
|---|
| 43 | buffer[1] = 0x80 | (utf8_char & 0x3F); | 
|---|
| 44 | utf8_char >>= 6; | 
|---|
| 45 | buffer[0] = 0xF0 | utf8_char; | 
|---|
| 46 | return 4; | 
|---|
| 47 | } | 
|---|
| 48 | } | 
|---|
| 49 |  | 
|---|
| 50 | }  // namespace strings_internal | 
|---|
| 51 | }  // namespace absl | 
|---|
| 52 |  | 
|---|