mirror of
https://github.com/kidfromjupiter/nearby.git
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40 lines
1.2 KiB
C++
40 lines
1.2 KiB
C++
// Copyright 2020 Google LLC
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// https://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include "platform/base/byte_utils.h"
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#include <cstdlib>
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#include "platform/base/base_input_stream.h"
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#include "absl/strings/str_format.h"
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namespace location {
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namespace nearby {
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std::string ByteUtils::ToFourDigitString(ByteArray& bytes) {
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int multiplier = 1;
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int hashCode = 0;
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BaseInputStream base_input_stream{bytes};
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while (base_input_stream.IsAvailable(1)) {
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auto byte = static_cast<int>(base_input_stream.ReadUint8());
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hashCode = (hashCode + byte * multiplier) % kHashBasePrime;
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multiplier = multiplier * kHashBaseMultiplier % kHashBasePrime;
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}
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return absl::StrFormat("%04d", abs(hashCode));
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}
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} // namespace nearby
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} // namespace location
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