4 /* pb.h: Common parts for nanopb library.
5 * Most of these are quite low-level stuff. For the high-level interface,
6 * see pb_encode.h or pb_decode.h
14 /* This just reduces memory requirements, but is not required. */
15 #define pb_packed __attribute__((packed))
20 /* Handly macro for suppressing unreferenced-parameter compiler warnings. */
22 #define UNUSED(x) (void)(x)
25 /* Number of required fields to keep track of
26 * (change here or on compiler command line). */
27 #ifndef PB_MAX_REQUIRED_FIELDS
28 #define PB_MAX_REQUIRED_FIELDS 64
31 /* List of possible field types. These are used in the autogenerated code.
32 * Least-significant 4 bits tell the scalar type
33 * Most-significant 4 bits specify repeated/required/packed etc.
35 * INT32 and UINT32 are treated the same, as are (U)INT64 and (S)FIXED*
36 * These types are simply casted to correct field type when they are
37 * assigned to the memory pointer.
38 * SINT* is different, though, because it is zig-zag coded.
42 /************************
43 * Field contents types *
44 ************************/
47 PB_LTYPE_VARINT = 0x00, /* int32, uint32, int64, uint64, bool, enum */
48 PB_LTYPE_SVARINT = 0x01, /* sint32, sint64 */
49 PB_LTYPE_FIXED32 = 0x02, /* fixed32, sfixed32, float */
50 PB_LTYPE_FIXED64 = 0x03, /* fixed64, sfixed64, double */
52 /* Marker for last packable field type. */
53 PB_LTYPE_LAST_PACKABLE = 0x03,
55 /* Byte array with pre-allocated buffer.
56 * data_size is the length of the allocated PB_BYTES_ARRAY structure. */
57 PB_LTYPE_BYTES = 0x04,
59 /* String with pre-allocated buffer.
60 * data_size is the maximum length. */
61 PB_LTYPE_STRING = 0x05,
64 * submsg_fields is pointer to field descriptions */
65 PB_LTYPE_SUBMESSAGE = 0x06,
67 /* Number of declared LTYPES */
74 /* Just the basic, write data at data_offset */
75 PB_HTYPE_REQUIRED = 0x00,
77 /* Write true at size_offset */
78 PB_HTYPE_OPTIONAL = 0x10,
80 /* Read to pre-allocated array
81 * Maximum number of entries is array_size,
82 * actual number is stored at size_offset */
83 PB_HTYPE_ARRAY = 0x20,
85 /* Works for all required/optional/repeated fields.
86 * data_offset points to pb_callback_t structure.
87 * LTYPE should be 0 (it is ignored, but sometimes
88 * used to speculatively index an array). */
89 PB_HTYPE_CALLBACK = 0x30
90 } pb_packed pb_type_t;
92 #define PB_HTYPE(x) ((x) & 0xF0)
93 #define PB_LTYPE(x) ((x) & 0x0F)
95 /* This structure is used in auto-generated constants
96 * to specify struct fields.
97 * You can change field sizes here if you need structures
98 * larger than 256 bytes or field tags larger than 256.
99 * The compiler should complain if your .proto has such
100 * structures ("initializer too large for type").
102 typedef struct _pb_field_t pb_field_t;
106 uint8_t data_offset; /* Offset of field data, relative to previous field. */
107 int8_t size_offset; /* Offset of array size or has-boolean, relative to data */
108 uint8_t data_size; /* Data size in bytes for a single item */
109 uint8_t array_size; /* Maximum number of entries in array */
111 /* Field definitions for submessage
112 * OR default value for all other non-array, non-callback types
113 * If null, then field will zeroed. */
117 /* This structure is used for 'bytes' arrays.
118 * It has the number of bytes in the beginning, and after that an array.
119 * Note that actual structs used will have a different length of bytes array.
126 /* This structure is used for giving the callback function.
127 * It is stored in the message structure and filled in by the method that
130 * The decoding callback will be given a limited-length stream
131 * If the wire type was string, the length is the length of the string.
132 * If the wire type was a varint/fixed32/fixed64, the length is the length
133 * of the actual value.
134 * The function may be called multiple times (especially for repeated types,
135 * but also otherwise if the message happens to contain the field multiple
138 * The encoding callback will receive the actual output stream.
139 * It should write all the data in one call, including the field tag and
140 * wire type. It can write multiple fields.
142 * The callback can be null if you want to skip a field.
144 typedef struct _pb_istream_t pb_istream_t;
145 typedef struct _pb_ostream_t pb_ostream_t;
146 typedef struct _pb_callback_t pb_callback_t;
147 struct _pb_callback_t {
149 bool (*decode)(pb_istream_t *stream, const pb_field_t *field, void *arg);
150 bool (*encode)(pb_ostream_t *stream, const pb_field_t *field, const void *arg);
153 /* Free arg for use by callback */
157 /* Wire types. Library user needs these only in encoder callbacks. */
165 /* These macros are used to declare pb_field_t's in the constant array. */
166 #define pb_membersize(st, m) (sizeof ((st*)0)->m)
167 #define pb_arraysize(st, m) (pb_membersize(st, m) / pb_membersize(st, m[0]))
168 #define pb_delta(st, m1, m2) ((int)offsetof(st, m1) - (int)offsetof(st, m2))
169 #define pb_delta_end(st, m1, m2) (offsetof(st, m1) - offsetof(st, m2) - pb_membersize(st, m2))
170 #define PB_LAST_FIELD {0,0,0,0}