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// Copyright 2024 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.
#include "absl/debugging/internal/utf8_for_code_point.h"
#include <cstdint>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace debugging_internal {
namespace {
// UTF-8 encoding bounds.
constexpr uint32_t kMinSurrogate = 0xd800, kMaxSurrogate = 0xdfff;
constexpr uint32_t kMax1ByteCodePoint = 0x7f;
constexpr uint32_t kMax2ByteCodePoint = 0x7ff;
constexpr uint32_t kMax3ByteCodePoint = 0xffff;
constexpr uint32_t kMaxCodePoint = 0x10ffff;
} // namespace
Utf8ForCodePoint::Utf8ForCodePoint(uint64_t code_point) {
if (code_point <= kMax1ByteCodePoint) {
length = 1;
bytes[0] = static_cast<char>(code_point);
return;
}
if (code_point <= kMax2ByteCodePoint) {
length = 2;
bytes[0] = static_cast<char>(0xc0 | (code_point >> 6));
bytes[1] = static_cast<char>(0x80 | (code_point & 0x3f));
return;
}
if (kMinSurrogate <= code_point && code_point <= kMaxSurrogate) return;
if (code_point <= kMax3ByteCodePoint) {
length = 3;
bytes[0] = static_cast<char>(0xe0 | (code_point >> 12));
bytes[1] = static_cast<char>(0x80 | ((code_point >> 6) & 0x3f));
bytes[2] = static_cast<char>(0x80 | (code_point & 0x3f));
return;
}
if (code_point > kMaxCodePoint) return;
length = 4;
bytes[0] = static_cast<char>(0xf0 | (code_point >> 18));
bytes[1] = static_cast<char>(0x80 | ((code_point >> 12) & 0x3f));
bytes[2] = static_cast<char>(0x80 | ((code_point >> 6) & 0x3f));
bytes[3] = static_cast<char>(0x80 | (code_point & 0x3f));
}
} // namespace debugging_internal
ABSL_NAMESPACE_END
} // namespace absl
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