chromium/services/tracing/public/cpp/perfetto/trace_packet_tokenizer.h

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SERVICES_TRACING_PUBLIC_CPP_PERFETTO_TRACE_PACKET_TOKENIZER_H_
#define SERVICES_TRACING_PUBLIC_CPP_PERFETTO_TRACE_PACKET_TOKENIZER_H_

#include <vector>

#include "base/component_export.h"
#include "third_party/abseil-cpp/absl/container/inlined_vector.h"
#include "third_party/perfetto/include/perfetto/protozero/proto_utils.h"

namespace perfetto {
class TracePacket;
}  // namespace perfetto

namespace tracing {

// Converts between a raw stream of perfetto::TracePacket bytes and a tokenized
// vector of delineated packets.
//
// The tracing service provides us with serialized proto bytes, while the
// Perfetto consumer expects a vector of TracePackets (i.e., without the field
// number and size header) without partial or truncated packets. To translate
// between the two, we find the position of each TracePacket and construct a
// vector pointing to the original data at the corresponding offsets.
//
// To make matters more complicated, mojo can split the data chunks
// arbitrarily, including in the middle of trace packets. To work around
// this, we tokenize as much data as we can and buffer any unprocessed bytes as
// long as needed.
class COMPONENT_EXPORT(TRACING_CPP) TracePacketTokenizer { … };

}  // namespace tracing

#endif  // SERVICES_TRACING_PUBLIC_CPP_PERFETTO_TRACE_PACKET_TOKENIZER_H_