4 /* pb_decode.h: Functions to decode protocol buffers. Depends on pb_decode.c.
5 * The main function is pb_decode. You will also need to create an input
6 * stream, which is easiest to do with pb_istream_from_buffer().
8 * You also need structures and their corresponding pb_field_t descriptions.
9 * These are usually generated from .proto-files with a script.
15 /* Lightweight input stream.
16 * You can provide a callback function for reading or use
17 * pb_istream_from_buffer.
20 * 1) Return false on IO errors. This will cause decoding to abort.
22 * 2) If buf is NULL, read but don't store bytes ("skip input").
24 * 3) You can use state to store your own data (e.g. buffer pointer),
25 * and rely on pb_read to verify that no-body reads past bytes_left.
27 * 4) Your callback may be used with substreams, in which case bytes_left
28 * is different than from the main stream. Don't use bytes_left to compute
33 bool (*callback)(pb_istream_t *stream, uint8_t *buf, size_t count);
34 void *state; /* Free field for use by callback implementation */
38 pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize);
39 bool pb_read(pb_istream_t *stream, uint8_t *buf, size_t count);
41 /* Decode from stream to destination struct.
42 * Returns true on success, false on any failure.
43 * The actual struct pointed to by dest must match the description in fields.
45 bool pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct);
47 /* --- Helper functions ---
48 * You may want to use these from your caller or callbacks.
51 bool pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof);
52 bool pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type);
54 bool pb_decode_varint(pb_istream_t *stream, uint64_t *dest);
56 bool pb_skip_varint(pb_istream_t *stream);
57 bool pb_skip_string(pb_istream_t *stream);
59 /* --- Field decoders ---
60 * Each decoder takes stream and field description, and a pointer to the field
61 * in the destination struct (dest = struct_addr + field->data_offset).
62 * For arrays, these functions are called repeatedly.
65 bool pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest);
66 bool pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
67 bool pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
68 bool pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest);
70 bool pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
71 bool pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
72 bool pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest);