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
9 #define NANOPB_VERSION nanopb-0.1.9
16 /* This just reduces memory requirements, but is not required. */
17 #define pb_packed __attribute__((packed))
22 /* Handly macro for suppressing unreferenced-parameter compiler warnings. */
24 #define UNUSED(x) (void)(x)
27 /* Compile-time assertion, used for checking compatible compilation options.
28 * If this fails on your compiler for some reason, use #define STATIC_ASSERT
31 #define STATIC_ASSERT(COND,MSG) typedef char STATIC_ASSERT_MSG(MSG, __LINE__, __COUNTER__)[(COND)?1:-1];
32 #define STATIC_ASSERT_MSG(MSG, LINE, COUNTER) STATIC_ASSERT_MSG_(MSG, LINE, COUNTER)
33 #define STATIC_ASSERT_MSG_(MSG, LINE, COUNTER) static_assertion_##MSG##LINE##COUNTER
36 /* Number of required fields to keep track of
37 * (change here or on compiler command line). */
38 #ifndef PB_MAX_REQUIRED_FIELDS
39 #define PB_MAX_REQUIRED_FIELDS 64
42 #if PB_MAX_REQUIRED_FIELDS < 64
43 #error You should not lower PB_MAX_REQUIRED_FIELDS from the default value (64).
46 /* List of possible field types. These are used in the autogenerated code.
47 * Least-significant 4 bits tell the scalar type
48 * Most-significant 4 bits specify repeated/required/packed etc.
50 * INT32 and UINT32 are treated the same, as are (U)INT64 and (S)FIXED*
51 * These types are simply casted to correct field type when they are
52 * assigned to the memory pointer.
53 * SINT* is different, though, because it is zig-zag coded.
57 /************************
58 * Field contents types *
59 ************************/
62 PB_LTYPE_VARINT = 0x00, /* int32, uint32, int64, uint64, bool, enum */
63 PB_LTYPE_SVARINT = 0x01, /* sint32, sint64 */
64 PB_LTYPE_FIXED32 = 0x02, /* fixed32, sfixed32, float */
65 PB_LTYPE_FIXED64 = 0x03, /* fixed64, sfixed64, double */
67 /* Marker for last packable field type. */
68 PB_LTYPE_LAST_PACKABLE = 0x03,
70 /* Byte array with pre-allocated buffer.
71 * data_size is the length of the allocated PB_BYTES_ARRAY structure. */
72 PB_LTYPE_BYTES = 0x04,
74 /* String with pre-allocated buffer.
75 * data_size is the maximum length. */
76 PB_LTYPE_STRING = 0x05,
79 * submsg_fields is pointer to field descriptions */
80 PB_LTYPE_SUBMESSAGE = 0x06,
82 /* Number of declared LTYPES */
90 /* Just the basic, write data at data_offset */
91 PB_HTYPE_REQUIRED = 0x00,
93 /* Write true at size_offset */
94 PB_HTYPE_OPTIONAL = 0x10,
96 /* Read to pre-allocated array
97 * Maximum number of entries is array_size,
98 * actual number is stored at size_offset */
99 PB_HTYPE_ARRAY = 0x20,
101 /* Works for all required/optional/repeated fields.
102 * data_offset points to pb_callback_t structure.
103 * LTYPE should be valid or 0 (it is ignored, but
104 * sometimes used to speculatively index an array). */
105 PB_HTYPE_CALLBACK = 0x30,
108 } pb_packed pb_type_t;
110 #define PB_HTYPE(x) ((x) & PB_HTYPE_MASK)
111 #define PB_LTYPE(x) ((x) & PB_LTYPE_MASK)
113 /* This structure is used in auto-generated constants
114 * to specify struct fields.
115 * You can change field sizes if you need structures
116 * larger than 256 bytes or field tags larger than 256.
117 * The compiler should complain if your .proto has such
118 * structures. Fix that by defining PB_FIELD_16BIT or
121 typedef struct _pb_field_t pb_field_t;
124 #if !defined(PB_FIELD_16BIT) && !defined(PB_FIELD_32BIT)
127 uint8_t data_offset; /* Offset of field data, relative to previous field. */
128 int8_t size_offset; /* Offset of array size or has-boolean, relative to data */
129 uint8_t data_size; /* Data size in bytes for a single item */
130 uint8_t array_size; /* Maximum number of entries in array */
131 #elif defined(PB_FIELD_16BIT) && !defined(PB_FIELD_32BIT)
147 /* Field definitions for submessage
148 * OR default value for all other non-array, non-callback types
149 * If null, then field will zeroed. */
153 /* This structure is used for 'bytes' arrays.
154 * It has the number of bytes in the beginning, and after that an array.
155 * Note that actual structs used will have a different length of bytes array.
157 struct _pb_bytes_array_t {
162 typedef struct _pb_bytes_array_t pb_bytes_array_t;
164 /* This structure is used for giving the callback function.
165 * It is stored in the message structure and filled in by the method that
168 * The decoding callback will be given a limited-length stream
169 * If the wire type was string, the length is the length of the string.
170 * If the wire type was a varint/fixed32/fixed64, the length is the length
171 * of the actual value.
172 * The function may be called multiple times (especially for repeated types,
173 * but also otherwise if the message happens to contain the field multiple
176 * The encoding callback will receive the actual output stream.
177 * It should write all the data in one call, including the field tag and
178 * wire type. It can write multiple fields.
180 * The callback can be null if you want to skip a field.
182 typedef struct _pb_istream_t pb_istream_t;
183 typedef struct _pb_ostream_t pb_ostream_t;
184 typedef struct _pb_callback_t pb_callback_t;
185 struct _pb_callback_t {
187 bool (*decode)(pb_istream_t *stream, const pb_field_t *field, void *arg);
188 bool (*encode)(pb_ostream_t *stream, const pb_field_t *field, const void *arg);
191 /* Free arg for use by callback */
195 /* Wire types. Library user needs these only in encoder callbacks. */
203 /* These macros are used to declare pb_field_t's in the constant array. */
204 #define pb_membersize(st, m) (sizeof ((st*)0)->m)
205 #define pb_arraysize(st, m) (pb_membersize(st, m) / pb_membersize(st, m[0]))
206 #define pb_delta(st, m1, m2) ((int)offsetof(st, m1) - (int)offsetof(st, m2))
207 #define pb_delta_end(st, m1, m2) (offsetof(st, m1) - offsetof(st, m2) - pb_membersize(st, m2))
208 #define PB_LAST_FIELD {0,(pb_type_t) 0,0,0,0,0,0}
210 /* These macros are used for giving out error messages.
211 * They are mostly a debugging aid; the main error information
212 * is the true/false return value from functions.
213 * Some code space can be saved by disabling the error
214 * messages if not used.
217 #define PB_RETURN_ERROR(stream,msg) return false
218 #define PB_GET_ERROR(stream) "(errmsg disabled)"
220 #define PB_RETURN_ERROR(stream,msg) \
222 if ((stream)->errmsg == NULL) \
223 (stream)->errmsg = (msg); \
226 #define PB_GET_ERROR(stream) ((stream)->errmsg ? (stream)->errmsg : "(none)")