1/*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_UTIL_PROTOBUF_H
18#define ANDROID_UTIL_PROTOBUF_H
19
20#include <stdint.h>
21
22namespace android {
23namespace util {
24
25const int FIELD_ID_SHIFT = 3;
26const uint8_t WIRE_TYPE_MASK = (1 << FIELD_ID_SHIFT) - 1;
27
28const uint8_t WIRE_TYPE_VARINT = 0;
29const uint8_t WIRE_TYPE_FIXED64 = 1;
30const uint8_t WIRE_TYPE_LENGTH_DELIMITED = 2;
31const uint8_t WIRE_TYPE_FIXED32 = 5;
32
33/**
34 * Read the wire type from varint, it is the smallest 3 bits.
35 */
36uint8_t read_wire_type(uint32_t varint);
37
38/**
39 * Read field id from varint, it is varint >> 3;
40 */
41uint32_t read_field_id(uint32_t varint);
42
43/**
44 * Get the size of a varint.
45 */
46size_t get_varint_size(uint64_t varint);
47
48/**
49 * Write a varint into the buffer. Return the next position to write at.
50 * There must be 10 bytes in the buffer.
51 */
52uint8_t* write_raw_varint(uint8_t* buf, uint64_t val);
53
54/**
55 * Write a protobuf WIRE_TYPE_LENGTH_DELIMITED header. Return the next position
56 * to write at. There must be 20 bytes in the buffer.
57 */
58uint8_t* write_length_delimited_tag_header(uint8_t* buf, uint32_t fieldId, size_t size);
59
60} // util
61} // android
62
63#endif  // ANDROID_UTIL_PROTOUBUF_H
64