/* * 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_BLOB_ENCODING_H_ #define LOGGING_RTC_EVENT_LOG_ENCODER_BLOB_ENCODING_H_ #include <stddef.h> #include <string> #include <vector> #include "absl/strings/string_view.h" namespace webrtc { // Encode/decode a sequence of strings, whose length is not known to be // discernable from the blob itself (i.e. without being transmitted OOB), // in a way that would allow us to separate them again on the decoding side. // The number of blobs is assumed to be transmitted OOB. For example, if // multiple sequences of different blobs are sent, but all sequences contain // the same number of blobs, it is beneficial to not encode the number of blobs. // // EncodeBlobs() must be given a non-empty vector. The blobs themselves may // be equal to "", though. // EncodeBlobs() may not fail. // EncodeBlobs() never returns the empty string. // // Calling DecodeBlobs() on an empty string, or with `num_of_blobs` set to 0, // is an error. // DecodeBlobs() returns an empty vector if it fails, e.g. due to a mismatch // between `num_of_blobs` and `encoded_blobs`, which can happen if // `encoded_blobs` is corrupted. // When successful, DecodeBlobs() returns a vector of string_view objects, // which refer to the original input (`encoded_blobs`), and therefore may // not outlive it. // // Note that the returned std::string might have been reserved for significantly // more memory than it ends up using. If the caller to EncodeBlobs() intends // to store the result long-term, they should consider shrink_to_fit()-ing it. std::string EncodeBlobs(const std::vector<std::string>& blobs); std::vector<absl::string_view> DecodeBlobs(absl::string_view encoded_blobs, size_t num_of_blobs); } // namespace webrtc #endif // LOGGING_RTC_EVENT_LOG_ENCODER_BLOB_ENCODING_H_