bounded_utf8_length_sequence.h | Explore in Territory

// 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.

#ifndef ABSL_DEBUGGING_INTERNAL_BOUNDED_UTF8_LENGTH_SEQUENCE_H_
#define ABSL_DEBUGGING_INTERNAL_BOUNDED_UTF8_LENGTH_SEQUENCE_H_

#include <cstdint>

#include "absl/base/config.h"
#include "absl/numeric/bits.h"

namespace absl {
ABSL_NAMESPACE_BEGIN
namespace debugging_internal {

// A sequence of up to max_elements integers between 1 and 4 inclusive, whose
// insertion operation computes the sum of all the elements before the insertion
// point.  This is useful in decoding Punycode, where one needs to know where in
// a UTF-8 byte stream the n-th code point begins.
//
// BoundedUtf8LengthSequence is async-signal-safe and suitable for use in
// symbolizing stack traces in a signal handler, provided max_elements is not
// improvidently large.  For inputs of lengths accepted by the Rust demangler,
// up to a couple hundred code points, InsertAndReturnSumOfPredecessors should
// run in a few dozen clock cycles, on par with the other arithmetic required
// for Punycode decoding.
template <uint32_t max_elements>
class BoundedUtf8LengthSequence { … };

}  // namespace debugging_internal
ABSL_NAMESPACE_END
}  // namespace absl

#endif  // ABSL_DEBUGGING_INTERNAL_BOUNDED_UTF8_LENGTH_SEQUENCE_H_
chromium/third_party/abseil-cpp/absl/debugging/internal/bounded_utf8_length_sequence.h
