fc8dc48020
git-subtree-dir: third_party/abseil_cpp git-subtree-mainline:ffb2ae54begit-subtree-split:768eb2ca28
50 lines
1.7 KiB
C++
50 lines
1.7 KiB
C++
// Copyright 2017 The Abseil Authors.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// https://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
//
|
|
// UTF8 utilities, implemented to reduce dependencies.
|
|
|
|
#ifndef ABSL_STRINGS_INTERNAL_UTF8_H_
|
|
#define ABSL_STRINGS_INTERNAL_UTF8_H_
|
|
|
|
#include <cstddef>
|
|
#include <cstdint>
|
|
|
|
#include "absl/base/config.h"
|
|
|
|
namespace absl {
|
|
ABSL_NAMESPACE_BEGIN
|
|
namespace strings_internal {
|
|
|
|
// For Unicode code points 0 through 0x10FFFF, EncodeUTF8Char writes
|
|
// out the UTF-8 encoding into buffer, and returns the number of chars
|
|
// it wrote.
|
|
//
|
|
// As described in https://tools.ietf.org/html/rfc3629#section-3 , the encodings
|
|
// are:
|
|
// 00 - 7F : 0xxxxxxx
|
|
// 80 - 7FF : 110xxxxx 10xxxxxx
|
|
// 800 - FFFF : 1110xxxx 10xxxxxx 10xxxxxx
|
|
// 10000 - 10FFFF : 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
|
|
//
|
|
// Values greater than 0x10FFFF are not supported and may or may not write
|
|
// characters into buffer, however never will more than kMaxEncodedUTF8Size
|
|
// bytes be written, regardless of the value of utf8_char.
|
|
enum { kMaxEncodedUTF8Size = 4 };
|
|
size_t EncodeUTF8Char(char *buffer, char32_t utf8_char);
|
|
|
|
} // namespace strings_internal
|
|
ABSL_NAMESPACE_END
|
|
} // namespace absl
|
|
|
|
#endif // ABSL_STRINGS_INTERNAL_UTF8_H_
|