af9a3c6676
Bug: webrtc:12338 Change-Id: I87d33f201d4acfb26ca1d2da8a52cc188ff2c791 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/226948 Commit-Queue: Artem Titov <titovartem@webrtc.org> Reviewed-by: Harald Alvestrand <hta@webrtc.org> Cr-Commit-Position: refs/heads/master@{#34609}
49 lines
1.9 KiB
C++
49 lines
1.9 KiB
C++
/*
|
|
* Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#ifndef LOGGING_RTC_EVENT_LOG_ENCODER_DELTA_ENCODING_H_
|
|
#define LOGGING_RTC_EVENT_LOG_ENCODER_DELTA_ENCODING_H_
|
|
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
#include "absl/types/optional.h"
|
|
|
|
namespace webrtc {
|
|
|
|
// Encode `values` as a sequence of deltas following on `base` and return it.
|
|
// If all of the values were equal to the base, an empty string will be
|
|
// returned; this is a valid encoding of that edge case.
|
|
// `base` is not guaranteed to be written into `output`, and must therefore
|
|
// be provided separately to the decoder.
|
|
// This function never fails.
|
|
// TODO(eladalon): Split into optional and non-optional variants (efficiency).
|
|
std::string EncodeDeltas(absl::optional<uint64_t> base,
|
|
const std::vector<absl::optional<uint64_t>>& values);
|
|
|
|
// EncodeDeltas() and DecodeDeltas() are inverse operations;
|
|
// invoking DecodeDeltas() over the output of EncodeDeltas(), will return
|
|
// the input originally given to EncodeDeltas().
|
|
// `num_of_deltas` must be greater than zero. If input is not a valid encoding
|
|
// of `num_of_deltas` elements based on `base`, the function returns an empty
|
|
// vector, which signals an error.
|
|
// TODO(eladalon): Split into optional and non-optional variants (efficiency).
|
|
std::vector<absl::optional<uint64_t>> DecodeDeltas(
|
|
const std::string& input,
|
|
absl::optional<uint64_t> base,
|
|
size_t num_of_deltas);
|
|
|
|
} // namespace webrtc
|
|
|
|
#endif // LOGGING_RTC_EVENT_LOG_ENCODER_DELTA_ENCODING_H_
|