1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
#ifndef _PB_ENCODE_H_
#define _PB_ENCODE_H_
/* pb_encode.h: Functions to encode protocol buffers. Depends on pb_encode.c.
* The main function is pb_encode. You also need an output stream, structures
* and their field descriptions (just like with pb_decode).
*/
#include <stdbool.h>
#include "pb.h"
#ifdef __cplusplus
extern "C" {
#endif
/* Lightweight output stream.
* You can provide callback for writing or use pb_ostream_from_buffer.
*
* Alternatively, callback can be NULL in which case the stream will just
* count the number of bytes that would have been written. In this case
* max_size is not checked.
*
* Rules for callback:
* 1) Return false on IO errors. This will cause encoding to abort.
*
* 2) You can use state to store your own data (e.g. buffer pointer).
*
* 3) pb_write will update bytes_written after your callback runs.
*
* 4) Substreams will modify max_size and bytes_written. Don't use them to
* calculate any pointers.
*/
struct _pb_ostream_t
{
#ifdef PB_BUFFER_ONLY
/* Callback pointer is not used in buffer-only configuration.
* Having an int pointer here allows binary compatibility but
* gives an error if someone tries to assign callback function.
* Also, NULL pointer marks a 'sizing stream' that does not
* write anything.
*/
int *callback;
#else
bool (*callback)(pb_ostream_t *stream, const uint8_t *buf, size_t count);
#endif
void *state; /* Free field for use by callback implementation */
size_t max_size; /* Limit number of output bytes written (or use SIZE_MAX). */
size_t bytes_written;
};
pb_ostream_t pb_ostream_from_buffer(uint8_t *buf, size_t bufsize);
bool pb_write(pb_ostream_t *stream, const uint8_t *buf, size_t count);
/* Encode struct to given output stream.
* Returns true on success, false on any failure.
* The actual struct pointed to by src_struct must match the description in fields.
* All required fields in the struct are assumed to have been filled in.
*/
bool pb_encode(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct);
/* --- Helper functions ---
* You may want to use these from your caller or callbacks.
*/
/* Encode field header based on LTYPE and field number defined in the field structure.
* Call this from the callback before writing out field contents. */
bool pb_encode_tag_for_field(pb_ostream_t *stream, const pb_field_t *field);
/* Encode field header by manually specifing wire type. You need to use this if
* you want to write out packed arrays from a callback field. */
bool pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, uint32_t field_number);
/* Encode an integer in the varint format.
* This works for bool, enum, int32, int64, uint32 and uint64 field types. */
bool pb_encode_varint(pb_ostream_t *stream, uint64_t value);
/* Encode an integer in the zig-zagged svarint format.
* This works for sint32 and sint64. */
bool pb_encode_svarint(pb_ostream_t *stream, int64_t value);
/* Encode a string or bytes type field. For strings, pass strlen(s) as size. */
bool pb_encode_string(pb_ostream_t *stream, const uint8_t *buffer, size_t size);
/* Encode a fixed32, sfixed32 or float value.
* You need to pass a pointer to a 4-byte wide C variable. */
bool pb_encode_fixed32(pb_ostream_t *stream, const void *value);
/* Encode a fixed64, sfixed64 or double value.
* You need to pass a pointer to a 8-byte wide C variable. */
bool pb_encode_fixed64(pb_ostream_t *stream, const void *value);
/* Encode a submessage field.
* You need to pass the pb_field_t array and pointer to struct, just like with pb_encode().
* This internally encodes the submessage twice, first to calculate message size and then to actually write it out.
*/
bool pb_encode_submessage(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct);
/* --- Internal functions ---
* These functions are not terribly useful for the average library user, but
* are exported to make the unit testing and extending nanopb easier.
*/
#ifdef NANOPB_INTERNALS
bool pb_enc_varint(pb_ostream_t *stream, const pb_field_t *field, const void *src);
bool pb_enc_svarint(pb_ostream_t *stream, const pb_field_t *field, const void *src);
bool pb_enc_fixed32(pb_ostream_t *stream, const pb_field_t *field, const void *src);
bool pb_enc_fixed64(pb_ostream_t *stream, const pb_field_t *field, const void *src);
bool pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src);
bool pb_enc_string(pb_ostream_t *stream, const pb_field_t *field, const void *src);
#endif
/* This function is not recommended for new programs. Use pb_encode_submessage()
* instead, it has the same functionality with a less confusing interface. */
bool pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field, const void *src);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif
|
