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792830c13f
Work towards https://github.com/flutter/flutter/issues/134969. These are all self-contained, so I bundled them all together. All fixes are generated by `clang-tidy --fix`, and manual search/replace if that wasn't sufficient.
58 lines
1.6 KiB
C++
58 lines
1.6 KiB
C++
// Copyright 2013 The Flutter Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef FLUTTER_FML_BASE32_H_
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#define FLUTTER_FML_BASE32_H_
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#include <string_view>
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#include <utility>
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#include "flutter/fml/logging.h"
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namespace fml {
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template <int from_length, int to_length, int buffer_length>
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class BitConverter {
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public:
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void Append(int bits) {
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FML_DCHECK(bits >= 0 && bits < (1 << from_length));
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FML_DCHECK(CanAppend());
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lower_free_bits_ -= from_length;
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buffer_ |= (bits << lower_free_bits_);
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}
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int Extract() {
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FML_DCHECK(CanExtract());
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int result = Peek();
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buffer_ = (buffer_ << to_length) & kMask;
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lower_free_bits_ += to_length;
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return result;
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}
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int Peek() const { return (buffer_ >> (buffer_length - to_length)); }
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int BitsAvailable() const { return buffer_length - lower_free_bits_; }
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bool CanAppend() const { return lower_free_bits_ >= from_length; }
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bool CanExtract() const { return BitsAvailable() >= to_length; }
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private:
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static_assert(buffer_length >= 2 * from_length);
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static_assert(buffer_length >= 2 * to_length);
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static_assert(buffer_length < sizeof(int) * 8);
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static constexpr int kMask = (1 << buffer_length) - 1;
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int buffer_ = 0;
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int lower_free_bits_ = buffer_length;
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};
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using Base32DecodeConverter = BitConverter<5, 8, 16>;
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using Base32EncodeConverter = BitConverter<8, 5, 16>;
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std::pair<bool, std::string> Base32Encode(std::string_view input);
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std::pair<bool, std::string> Base32Decode(const std::string& input);
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} // namespace fml
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#endif // FLUTTER_FML_BASE32_H_
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