1/* Common parts of the nanopb library. Most of these are quite low-level
2 * stuff. For the high-level interface, see pb_encode.h and pb_decode.h.
3 */
4
5#ifndef _PB_H_
6#define _PB_H_
7
8/*****************************************************************
9 * Nanopb compilation time options. You can change these here by *
10 * uncommenting the lines, or on the compiler command line.      *
11 *****************************************************************/
12
13/* Enable support for dynamically allocated fields */
14/* #define PB_ENABLE_MALLOC 1 */
15
16/* Define this if your CPU architecture is big endian, i.e. it
17 * stores the most-significant byte first. */
18/* #define __BIG_ENDIAN__ 1 */
19
20/* Increase the number of required fields that are tracked.
21 * A compiler warning will tell if you need this. */
22/* #define PB_MAX_REQUIRED_FIELDS 256 */
23
24/* Add support for tag numbers > 255 and fields larger than 255 bytes. */
25/* #define PB_FIELD_16BIT 1 */
26
27/* Add support for tag numbers > 65536 and fields larger than 65536 bytes. */
28/* #define PB_FIELD_32BIT 1 */
29
30/* Disable support for error messages in order to save some code space. */
31/* #define PB_NO_ERRMSG 1 */
32
33/* Disable support for custom streams (support only memory buffers). */
34/* #define PB_BUFFER_ONLY 1 */
35
36/* Switch back to the old-style callback function signature.
37 * This was the default until nanopb-0.2.1. */
38/* #define PB_OLD_CALLBACK_STYLE */
39
40
41/******************************************************************
42 * You usually don't need to change anything below this line.     *
43 * Feel free to look around and use the defined macros, though.   *
44 ******************************************************************/
45
46
47/* Version of the nanopb library. Just in case you want to check it in
48 * your own program. */
49#define NANOPB_VERSION nanopb-0.2.8-dev
50
51/* Include all the system headers needed by nanopb. You will need the
52 * definitions of the following:
53 * - strlen, memcpy, memset functions
54 * - [u]int8_t, [u]int16_t, [u]int32_t, [u]int64_t
55 * - size_t
56 * - bool
57 *
58 * If you don't have the standard header files, you can instead provide
59 * a custom header that defines or includes all this. In that case,
60 * define PB_SYSTEM_HEADER to the path of this file.
61 */
62#ifdef PB_SYSTEM_HEADER
63#include PB_SYSTEM_HEADER
64#else
65#include <stdint.h>
66#include <stddef.h>
67#include <stdbool.h>
68#include <string.h>
69
70#ifdef PB_ENABLE_MALLOC
71#include <stdlib.h>
72#endif
73#endif
74
75/* Macro for defining packed structures (compiler dependent).
76 * This just reduces memory requirements, but is not required.
77 */
78#if defined(__GNUC__) || defined(__clang__)
79    /* For GCC and clang */
80#   define PB_PACKED_STRUCT_START
81#   define PB_PACKED_STRUCT_END
82#   define pb_packed __attribute__((packed))
83#elif defined(__ICCARM__)
84    /* For IAR ARM compiler */
85#   define PB_PACKED_STRUCT_START _Pragma("pack(push, 1)")
86#   define PB_PACKED_STRUCT_END _Pragma("pack(pop)")
87#   define pb_packed
88#elif defined(_MSC_VER) && (_MSC_VER >= 1500)
89    /* For Microsoft Visual C++ */
90#   define PB_PACKED_STRUCT_START __pragma(pack(push, 1))
91#   define PB_PACKED_STRUCT_END __pragma(pack(pop))
92#   define pb_packed
93#else
94    /* Unknown compiler */
95#   define PB_PACKED_STRUCT_START
96#   define PB_PACKED_STRUCT_END
97#   define pb_packed
98#endif
99
100/* Handly macro for suppressing unreferenced-parameter compiler warnings. */
101#ifndef UNUSED
102#define UNUSED(x) (void)(x)
103#endif
104
105/* Compile-time assertion, used for checking compatible compilation options.
106 * If this does not work properly on your compiler, use #define STATIC_ASSERT
107 * to disable it.
108 *
109 * But before doing that, check carefully the error message / place where it
110 * comes from to see if the error has a real cause. Unfortunately the error
111 * message is not always very clear to read, but you can see the reason better
112 * in the place where the STATIC_ASSERT macro was called.
113 */
114#ifndef STATIC_ASSERT
115#define STATIC_ASSERT(COND,MSG) typedef char STATIC_ASSERT_MSG(MSG, __LINE__, __COUNTER__)[(COND)?1:-1];
116#define STATIC_ASSERT_MSG(MSG, LINE, COUNTER) STATIC_ASSERT_MSG_(MSG, LINE, COUNTER)
117#define STATIC_ASSERT_MSG_(MSG, LINE, COUNTER) static_assertion_##MSG##LINE##COUNTER
118#endif
119
120/* Number of required fields to keep track of. */
121#ifndef PB_MAX_REQUIRED_FIELDS
122#define PB_MAX_REQUIRED_FIELDS 64
123#endif
124
125#if PB_MAX_REQUIRED_FIELDS < 64
126#error You should not lower PB_MAX_REQUIRED_FIELDS from the default value (64).
127#endif
128
129/* List of possible field types. These are used in the autogenerated code.
130 * Least-significant 4 bits tell the scalar type
131 * Most-significant 4 bits specify repeated/required/packed etc.
132 */
133
134typedef uint8_t pb_type_t;
135
136/**** Field data types ****/
137
138/* Numeric types */
139#define PB_LTYPE_VARINT  0x00 /* int32, int64, enum, bool */
140#define PB_LTYPE_UVARINT 0x01 /* uint32, uint64 */
141#define PB_LTYPE_SVARINT 0x02 /* sint32, sint64 */
142#define PB_LTYPE_FIXED32 0x03 /* fixed32, sfixed32, float */
143#define PB_LTYPE_FIXED64 0x04 /* fixed64, sfixed64, double */
144
145/* Marker for last packable field type. */
146#define PB_LTYPE_LAST_PACKABLE 0x04
147
148/* Byte array with pre-allocated buffer.
149 * data_size is the length of the allocated PB_BYTES_ARRAY structure. */
150#define PB_LTYPE_BYTES 0x05
151
152/* String with pre-allocated buffer.
153 * data_size is the maximum length. */
154#define PB_LTYPE_STRING 0x06
155
156/* Submessage
157 * submsg_fields is pointer to field descriptions */
158#define PB_LTYPE_SUBMESSAGE 0x07
159
160/* Extension pseudo-field
161 * The field contains a pointer to pb_extension_t */
162#define PB_LTYPE_EXTENSION 0x08
163
164/* Number of declared LTYPES */
165#define PB_LTYPES_COUNT 9
166#define PB_LTYPE_MASK 0x0F
167
168/**** Field repetition rules ****/
169
170#define PB_HTYPE_REQUIRED 0x00
171#define PB_HTYPE_OPTIONAL 0x10
172#define PB_HTYPE_REPEATED 0x20
173#define PB_HTYPE_MASK     0x30
174
175/**** Field allocation types ****/
176
177#define PB_ATYPE_STATIC   0x00
178#define PB_ATYPE_POINTER  0x80
179#define PB_ATYPE_CALLBACK 0x40
180#define PB_ATYPE_MASK     0xC0
181
182#define PB_ATYPE(x) ((x) & PB_ATYPE_MASK)
183#define PB_HTYPE(x) ((x) & PB_HTYPE_MASK)
184#define PB_LTYPE(x) ((x) & PB_LTYPE_MASK)
185
186/* Data type used for storing sizes of struct fields
187 * and array counts.
188 */
189#if defined(PB_FIELD_32BIT)
190    typedef uint32_t pb_size_t;
191    typedef int32_t pb_ssize_t;
192#elif defined(PB_FIELD_16BIT)
193    typedef uint16_t pb_size_t;
194    typedef int16_t pb_ssize_t;
195#else
196    typedef uint8_t pb_size_t;
197    typedef int8_t pb_ssize_t;
198#endif
199
200/* This structure is used in auto-generated constants
201 * to specify struct fields.
202 * You can change field sizes if you need structures
203 * larger than 256 bytes or field tags larger than 256.
204 * The compiler should complain if your .proto has such
205 * structures. Fix that by defining PB_FIELD_16BIT or
206 * PB_FIELD_32BIT.
207 */
208PB_PACKED_STRUCT_START
209typedef struct _pb_field_t pb_field_t;
210struct _pb_field_t {
211    pb_size_t tag;
212    pb_type_t type;
213    pb_size_t data_offset; /* Offset of field data, relative to previous field. */
214    pb_ssize_t size_offset; /* Offset of array size or has-boolean, relative to data */
215    pb_size_t data_size; /* Data size in bytes for a single item */
216    pb_size_t array_size; /* Maximum number of entries in array */
217
218    /* Field definitions for submessage
219     * OR default value for all other non-array, non-callback types
220     * If null, then field will zeroed. */
221    const void *ptr;
222} pb_packed;
223PB_PACKED_STRUCT_END
224
225/* Make sure that the standard integer types are of the expected sizes.
226 * All kinds of things may break otherwise.. atleast all fixed* types.
227 *
228 * If you get errors here, it probably means that your stdint.h is not
229 * correct for your platform.
230 */
231STATIC_ASSERT(sizeof(int8_t) == 1, INT8_T_WRONG_SIZE)
232STATIC_ASSERT(sizeof(uint8_t) == 1, UINT8_T_WRONG_SIZE)
233STATIC_ASSERT(sizeof(int16_t) == 2, INT16_T_WRONG_SIZE)
234STATIC_ASSERT(sizeof(uint16_t) == 2, UINT16_T_WRONG_SIZE)
235STATIC_ASSERT(sizeof(int32_t) == 4, INT32_T_WRONG_SIZE)
236STATIC_ASSERT(sizeof(uint32_t) == 4, UINT32_T_WRONG_SIZE)
237STATIC_ASSERT(sizeof(int64_t) == 8, INT64_T_WRONG_SIZE)
238STATIC_ASSERT(sizeof(uint64_t) == 8, UINT64_T_WRONG_SIZE)
239
240/* This structure is used for 'bytes' arrays.
241 * It has the number of bytes in the beginning, and after that an array.
242 * Note that actual structs used will have a different length of bytes array.
243 */
244#define PB_BYTES_ARRAY_T(n) struct { size_t size; uint8_t bytes[n]; }
245#define PB_BYTES_ARRAY_T_ALLOCSIZE(n) ((size_t)n + offsetof(pb_bytes_array_t, bytes))
246
247struct _pb_bytes_array_t {
248    size_t size;
249    uint8_t bytes[1];
250};
251typedef struct _pb_bytes_array_t pb_bytes_array_t;
252
253/* This structure is used for giving the callback function.
254 * It is stored in the message structure and filled in by the method that
255 * calls pb_decode.
256 *
257 * The decoding callback will be given a limited-length stream
258 * If the wire type was string, the length is the length of the string.
259 * If the wire type was a varint/fixed32/fixed64, the length is the length
260 * of the actual value.
261 * The function may be called multiple times (especially for repeated types,
262 * but also otherwise if the message happens to contain the field multiple
263 * times.)
264 *
265 * The encoding callback will receive the actual output stream.
266 * It should write all the data in one call, including the field tag and
267 * wire type. It can write multiple fields.
268 *
269 * The callback can be null if you want to skip a field.
270 */
271typedef struct _pb_istream_t pb_istream_t;
272typedef struct _pb_ostream_t pb_ostream_t;
273typedef struct _pb_callback_t pb_callback_t;
274struct _pb_callback_t {
275#ifdef PB_OLD_CALLBACK_STYLE
276    /* Deprecated since nanopb-0.2.1 */
277    union {
278        bool (*decode)(pb_istream_t *stream, const pb_field_t *field, void *arg);
279        bool (*encode)(pb_ostream_t *stream, const pb_field_t *field, const void *arg);
280    } funcs;
281#else
282    /* New function signature, which allows modifying arg contents in callback. */
283    union {
284        bool (*decode)(pb_istream_t *stream, const pb_field_t *field, void **arg);
285        bool (*encode)(pb_ostream_t *stream, const pb_field_t *field, void * const *arg);
286    } funcs;
287#endif
288
289    /* Free arg for use by callback */
290    void *arg;
291};
292
293/* Wire types. Library user needs these only in encoder callbacks. */
294typedef enum {
295    PB_WT_VARINT = 0,
296    PB_WT_64BIT  = 1,
297    PB_WT_STRING = 2,
298    PB_WT_32BIT  = 5
299} pb_wire_type_t;
300
301/* Structure for defining the handling of unknown/extension fields.
302 * Usually the pb_extension_type_t structure is automatically generated,
303 * while the pb_extension_t structure is created by the user. However,
304 * if you want to catch all unknown fields, you can also create a custom
305 * pb_extension_type_t with your own callback.
306 */
307typedef struct _pb_extension_type_t pb_extension_type_t;
308typedef struct _pb_extension_t pb_extension_t;
309struct _pb_extension_type_t {
310    /* Called for each unknown field in the message.
311     * If you handle the field, read off all of its data and return true.
312     * If you do not handle the field, do not read anything and return true.
313     * If you run into an error, return false.
314     * Set to NULL for default handler.
315     */
316    bool (*decode)(pb_istream_t *stream, pb_extension_t *extension,
317                   uint32_t tag, pb_wire_type_t wire_type);
318
319    /* Called once after all regular fields have been encoded.
320     * If you have something to write, do so and return true.
321     * If you do not have anything to write, just return true.
322     * If you run into an error, return false.
323     * Set to NULL for default handler.
324     */
325    bool (*encode)(pb_ostream_t *stream, const pb_extension_t *extension);
326
327    /* Free field for use by the callback. */
328    const void *arg;
329};
330
331struct _pb_extension_t {
332    /* Type describing the extension field. Usually you'll initialize
333     * this to a pointer to the automatically generated structure. */
334    const pb_extension_type_t *type;
335
336    /* Destination for the decoded data. This must match the datatype
337     * of the extension field. */
338    void *dest;
339
340    /* Pointer to the next extension handler, or NULL.
341     * If this extension does not match a field, the next handler is
342     * automatically called. */
343    pb_extension_t *next;
344
345    /* The decoder sets this to true if the extension was found.
346     * Ignored for encoding. */
347    bool found;
348};
349
350/* Memory allocation functions to use. You can define pb_realloc and
351 * pb_free to custom functions if you want. */
352#ifdef PB_ENABLE_MALLOC
353#   ifndef pb_realloc
354#       define pb_realloc(ptr, size) realloc(ptr, size)
355#   endif
356#   ifndef pb_free
357#       define pb_free(ptr) free(ptr)
358#   endif
359#endif
360
361/* These macros are used to declare pb_field_t's in the constant array. */
362/* Size of a structure member, in bytes. */
363#define pb_membersize(st, m) (sizeof ((st*)0)->m)
364/* Number of entries in an array. */
365#define pb_arraysize(st, m) (pb_membersize(st, m) / pb_membersize(st, m[0]))
366/* Delta from start of one member to the start of another member. */
367#define pb_delta(st, m1, m2) ((int)offsetof(st, m1) - (int)offsetof(st, m2))
368/* Marks the end of the field list */
369#define PB_LAST_FIELD {0,(pb_type_t) 0,0,0,0,0,0}
370
371/* Macros for filling in the data_offset field */
372/* data_offset for first field in a message */
373#define PB_DATAOFFSET_FIRST(st, m1, m2) (offsetof(st, m1))
374/* data_offset for subsequent fields */
375#define PB_DATAOFFSET_OTHER(st, m1, m2) (offsetof(st, m1) - offsetof(st, m2) - pb_membersize(st, m2))
376/* Choose first/other based on m1 == m2 (deprecated, remains for backwards compatibility) */
377#define PB_DATAOFFSET_CHOOSE(st, m1, m2) (int)(offsetof(st, m1) == offsetof(st, m2) \
378                                  ? PB_DATAOFFSET_FIRST(st, m1, m2) \
379                                  : PB_DATAOFFSET_OTHER(st, m1, m2))
380
381/* Required fields are the simplest. They just have delta (padding) from
382 * previous field end, and the size of the field. Pointer is used for
383 * submessages and default values.
384 */
385#define PB_REQUIRED_STATIC(tag, st, m, fd, ltype, ptr) \
386    {tag, PB_ATYPE_STATIC | PB_HTYPE_REQUIRED | ltype, \
387    fd, 0, pb_membersize(st, m), 0, ptr}
388
389/* Optional fields add the delta to the has_ variable. */
390#define PB_OPTIONAL_STATIC(tag, st, m, fd, ltype, ptr) \
391    {tag, PB_ATYPE_STATIC | PB_HTYPE_OPTIONAL | ltype, \
392    fd, \
393    pb_delta(st, has_ ## m, m), \
394    pb_membersize(st, m), 0, ptr}
395
396/* Repeated fields have a _count field and also the maximum number of entries. */
397#define PB_REPEATED_STATIC(tag, st, m, fd, ltype, ptr) \
398    {tag, PB_ATYPE_STATIC | PB_HTYPE_REPEATED | ltype, \
399    fd, \
400    pb_delta(st, m ## _count, m), \
401    pb_membersize(st, m[0]), \
402    pb_arraysize(st, m), ptr}
403
404/* Allocated fields carry the size of the actual data, not the pointer */
405#define PB_REQUIRED_POINTER(tag, st, m, fd, ltype, ptr) \
406    {tag, PB_ATYPE_POINTER | PB_HTYPE_REQUIRED | ltype, \
407    fd, 0, pb_membersize(st, m[0]), 0, ptr}
408
409/* Optional fields don't need a has_ variable, as information would be redundant */
410#define PB_OPTIONAL_POINTER(tag, st, m, fd, ltype, ptr) \
411    {tag, PB_ATYPE_POINTER | PB_HTYPE_OPTIONAL | ltype, \
412    fd, 0, pb_membersize(st, m[0]), 0, ptr}
413
414/* Repeated fields have a _count field and a pointer to array of pointers */
415#define PB_REPEATED_POINTER(tag, st, m, fd, ltype, ptr) \
416    {tag, PB_ATYPE_POINTER | PB_HTYPE_REPEATED | ltype, \
417    fd, pb_delta(st, m ## _count, m), \
418    pb_membersize(st, m[0]), 0, ptr}
419
420/* Callbacks are much like required fields except with special datatype. */
421#define PB_REQUIRED_CALLBACK(tag, st, m, fd, ltype, ptr) \
422    {tag, PB_ATYPE_CALLBACK | PB_HTYPE_REQUIRED | ltype, \
423    fd, 0, pb_membersize(st, m), 0, ptr}
424
425#define PB_OPTIONAL_CALLBACK(tag, st, m, fd, ltype, ptr) \
426    {tag, PB_ATYPE_CALLBACK | PB_HTYPE_OPTIONAL | ltype, \
427    fd, 0, pb_membersize(st, m), 0, ptr}
428
429#define PB_REPEATED_CALLBACK(tag, st, m, fd, ltype, ptr) \
430    {tag, PB_ATYPE_CALLBACK | PB_HTYPE_REPEATED | ltype, \
431    fd, 0, pb_membersize(st, m), 0, ptr}
432
433/* Optional extensions don't have the has_ field, as that would be redundant. */
434#define PB_OPTEXT_STATIC(tag, st, m, fd, ltype, ptr) \
435    {tag, PB_ATYPE_STATIC | PB_HTYPE_OPTIONAL | ltype, \
436    0, \
437    0, \
438    pb_membersize(st, m), 0, ptr}
439
440#define PB_OPTEXT_CALLBACK(tag, st, m, fd, ltype, ptr) \
441    {tag, PB_ATYPE_CALLBACK | PB_HTYPE_OPTIONAL | ltype, \
442    0, 0, pb_membersize(st, m), 0, ptr}
443
444/* The mapping from protobuf types to LTYPEs is done using these macros. */
445#define PB_LTYPE_MAP_BOOL       PB_LTYPE_VARINT
446#define PB_LTYPE_MAP_BYTES      PB_LTYPE_BYTES
447#define PB_LTYPE_MAP_DOUBLE     PB_LTYPE_FIXED64
448#define PB_LTYPE_MAP_ENUM       PB_LTYPE_VARINT
449#define PB_LTYPE_MAP_FIXED32    PB_LTYPE_FIXED32
450#define PB_LTYPE_MAP_FIXED64    PB_LTYPE_FIXED64
451#define PB_LTYPE_MAP_FLOAT      PB_LTYPE_FIXED32
452#define PB_LTYPE_MAP_INT32      PB_LTYPE_VARINT
453#define PB_LTYPE_MAP_INT64      PB_LTYPE_VARINT
454#define PB_LTYPE_MAP_MESSAGE    PB_LTYPE_SUBMESSAGE
455#define PB_LTYPE_MAP_SFIXED32   PB_LTYPE_FIXED32
456#define PB_LTYPE_MAP_SFIXED64   PB_LTYPE_FIXED64
457#define PB_LTYPE_MAP_SINT32     PB_LTYPE_SVARINT
458#define PB_LTYPE_MAP_SINT64     PB_LTYPE_SVARINT
459#define PB_LTYPE_MAP_STRING     PB_LTYPE_STRING
460#define PB_LTYPE_MAP_UINT32     PB_LTYPE_UVARINT
461#define PB_LTYPE_MAP_UINT64     PB_LTYPE_UVARINT
462#define PB_LTYPE_MAP_EXTENSION  PB_LTYPE_EXTENSION
463
464/* This is the actual macro used in field descriptions.
465 * It takes these arguments:
466 * - Field tag number
467 * - Field type:   BOOL, BYTES, DOUBLE, ENUM, FIXED32, FIXED64,
468 *                 FLOAT, INT32, INT64, MESSAGE, SFIXED32, SFIXED64
469 *                 SINT32, SINT64, STRING, UINT32, UINT64 or EXTENSION
470 * - Field rules:  REQUIRED, OPTIONAL or REPEATED
471 * - Allocation:   STATIC or CALLBACK
472 * - Message name
473 * - Field name
474 * - Previous field name (or field name again for first field)
475 * - Pointer to default value or submsg fields.
476 */
477
478#define PB_FIELD(tag, type, rules, allocation, message, field, prevfield, ptr) \
479    PB_ ## rules ## _ ## allocation(tag, message, field, \
480        PB_DATAOFFSET_CHOOSE(message, field, prevfield), \
481        PB_LTYPE_MAP_ ## type, ptr)
482
483/* This is a new version of the macro used by nanopb generator from
484 * version 0.2.3 onwards. It avoids the use of a ternary expression in
485 * the initialization, which confused some compilers.
486 *
487 * - Placement: FIRST or OTHER, depending on if this is the first field in structure.
488 *
489 */
490#define PB_FIELD2(tag, type, rules, allocation, placement, message, field, prevfield, ptr) \
491    PB_ ## rules ## _ ## allocation(tag, message, field, \
492        PB_DATAOFFSET_ ## placement(message, field, prevfield), \
493        PB_LTYPE_MAP_ ## type, ptr)
494
495
496/* These macros are used for giving out error messages.
497 * They are mostly a debugging aid; the main error information
498 * is the true/false return value from functions.
499 * Some code space can be saved by disabling the error
500 * messages if not used.
501 */
502#ifdef PB_NO_ERRMSG
503#define PB_RETURN_ERROR(stream,msg) \
504    do {\
505        UNUSED(stream); \
506        return false; \
507    } while(0)
508#define PB_GET_ERROR(stream) "(errmsg disabled)"
509#else
510#define PB_RETURN_ERROR(stream,msg) \
511    do {\
512        if ((stream)->errmsg == NULL) \
513            (stream)->errmsg = (msg); \
514        return false; \
515    } while(0)
516#define PB_GET_ERROR(stream) ((stream)->errmsg ? (stream)->errmsg : "(none)")
517#endif
518
519#endif
520