chromium/third_party/perfetto/include/perfetto/public/pb_utils.h

/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef INCLUDE_PERFETTO_PUBLIC_PB_UTILS_H_
#define INCLUDE_PERFETTO_PUBLIC_PB_UTILS_H_

#include <assert.h>
#include <stdint.h>
#include <string.h>

#include "perfetto/public/compiler.h"

// Type of fields that can be found in a protobuf serialized message.
enum PerfettoPbWireType { … };

// Creates a field tag, which encodes the field type and the field id.
static inline uint32_t PerfettoPbMakeTag(int32_t field_id,
                                         enum PerfettoPbWireType wire_type) { … }

enum { … };

// Encodes `value` as a VarInt into `*dst`.
//
// `dst` must point into a buffer big enough to represent `value`:
// PERFETTO_PB_VARINT_MAX_SIZE_* can help.
static inline uint8_t* PerfettoPbWriteVarInt(uint64_t value, uint8_t* dst) { … }

// Encodes `value` as a fixed32 (little endian) into `*dst`.
//
// `dst` must point into a buffer with at least 4 bytes of space.
static inline uint8_t* PerfettoPbWriteFixed32(uint32_t value, uint8_t* buf) { … }

// Encodes `value` as a fixed32 (little endian) into `*dst`.
//
// `dst` must point into a buffer with at least 8 bytes of space.
static inline uint8_t* PerfettoPbWriteFixed64(uint64_t value, uint8_t* buf) { … }

// Parses a VarInt from the encoded buffer [start, end). |end| is STL-style and
// points one byte past the end of buffer.
// The parsed int value is stored in the output arg |value|. Returns a pointer
// to the next unconsumed byte (so start < retval <= end) or |start| if the
// VarInt could not be fully parsed because there was not enough space in the
// buffer.
static inline const uint8_t* PerfettoPbParseVarInt(const uint8_t* start,
                                                   const uint8_t* end,
                                                   uint64_t* out_value) { … }

static inline uint32_t PerfettoPbZigZagEncode32(int32_t value) { … }

static inline uint64_t PerfettoPbZigZagEncode64(int64_t value) { … }

static inline int32_t PerfettoPbZigZagDecode32(uint32_t value) { … }

static inline int64_t PerfettoPbZigZagDecode64(uint64_t value) { … }

static inline uint64_t PerfettoPbDoubleToFixed64(double value) { … }

static inline uint32_t PerfettoPbFloatToFixed32(float value) { … }

#endif  // INCLUDE_PERFETTO_PUBLIC_PB_UTILS_H_