1 /* pb_decode.c -- decode a protobuf using minimal resources
3 * 2011 Petteri Aimonen <jpa@kapsi.fi>
6 /* Use the GCC warn_unused_result attribute to check that all return values
7 * are propagated correctly. On other compilers and gcc before 3.4.0 just
8 * ignore the annotation.
10 #if !defined(__GNUC__) || ( __GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
13 #define checkreturn __attribute__((warn_unused_result))
17 #include "pb_decode.h"
18 #include "pb_common.h"
20 /**************************************
21 * Declarations internal to this file *
22 **************************************/
24 typedef bool (*pb_decoder_t)(pb_istream_t *stream, const pb_field_t *field, void *dest) checkreturn;
26 static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count);
27 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest);
28 static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, uint8_t *buf, size_t *size);
29 static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
30 static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
31 static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
32 static void iter_from_extension(pb_field_iter_t *iter, pb_extension_t *extension);
33 static bool checkreturn default_extension_decoder(pb_istream_t *stream, pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type);
34 static bool checkreturn decode_extension(pb_istream_t *stream, uint32_t tag, pb_wire_type_t wire_type, pb_field_iter_t *iter);
35 static bool checkreturn find_extension_field(pb_field_iter_t *iter);
36 static void pb_field_set_to_default(pb_field_iter_t *iter);
37 static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct);
38 static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest);
39 static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
40 static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
41 static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
42 static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest);
43 static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
44 static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
45 static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest);
46 static bool checkreturn pb_skip_varint(pb_istream_t *stream);
47 static bool checkreturn pb_skip_string(pb_istream_t *stream);
49 #ifdef PB_ENABLE_MALLOC
50 static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size);
51 static bool checkreturn pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *iter);
52 static void pb_release_single_field(const pb_field_iter_t *iter);
55 /* --- Function pointers to field decoders ---
56 * Order in the array must match pb_action_t LTYPE numbering.
58 static const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT] = {
71 /*******************************
72 * pb_istream_t implementation *
73 *******************************/
75 static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count)
77 uint8_t *source = (uint8_t*)stream->state;
78 stream->state = source + count;
89 bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
91 #ifndef PB_BUFFER_ONLY
92 if (buf == NULL && stream->callback != buf_read)
94 /* Skip input bytes */
98 if (!pb_read(stream, tmp, 16))
104 return pb_read(stream, tmp, count);
108 if (stream->bytes_left < count)
109 PB_RETURN_ERROR(stream, "end-of-stream");
111 #ifndef PB_BUFFER_ONLY
112 if (!stream->callback(stream, buf, count))
113 PB_RETURN_ERROR(stream, "io error");
115 if (!buf_read(stream, buf, count))
119 stream->bytes_left -= count;
123 /* Read a single byte from input stream. buf may not be NULL.
124 * This is an optimization for the varint decoding. */
125 static bool checkreturn pb_readbyte(pb_istream_t *stream, uint8_t *buf)
127 if (stream->bytes_left == 0)
128 PB_RETURN_ERROR(stream, "end-of-stream");
130 #ifndef PB_BUFFER_ONLY
131 if (!stream->callback(stream, buf, 1))
132 PB_RETURN_ERROR(stream, "io error");
134 *buf = *(uint8_t*)stream->state;
135 stream->state = (uint8_t*)stream->state + 1;
138 stream->bytes_left--;
143 pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize)
146 #ifdef PB_BUFFER_ONLY
147 stream.callback = NULL;
149 stream.callback = &buf_read;
152 stream.bytes_left = bufsize;
154 stream.errmsg = NULL;
159 /********************
161 ********************/
163 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
168 if (!pb_readbyte(stream, &byte))
171 if ((byte & 0x80) == 0)
173 /* Quick case, 1 byte value */
180 result = byte & 0x7F;
185 PB_RETURN_ERROR(stream, "varint overflow");
187 if (!pb_readbyte(stream, &byte))
190 result |= (uint32_t)(byte & 0x7F) << bitpos;
191 bitpos = (uint8_t)(bitpos + 7);
192 } while (byte & 0x80);
199 bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
208 PB_RETURN_ERROR(stream, "varint overflow");
210 if (!pb_readbyte(stream, &byte))
213 result |= (uint64_t)(byte & 0x7F) << bitpos;
214 bitpos = (uint8_t)(bitpos + 7);
215 } while (byte & 0x80);
221 bool checkreturn pb_skip_varint(pb_istream_t *stream)
226 if (!pb_read(stream, &byte, 1))
228 } while (byte & 0x80);
232 bool checkreturn pb_skip_string(pb_istream_t *stream)
235 if (!pb_decode_varint32(stream, &length))
238 return pb_read(stream, NULL, length);
241 bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof)
245 *wire_type = (pb_wire_type_t) 0;
248 if (!pb_decode_varint32(stream, &temp))
250 if (stream->bytes_left == 0)
258 *eof = true; /* Special feature: allow 0-terminated messages. */
263 *wire_type = (pb_wire_type_t)(temp & 7);
267 bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
271 case PB_WT_VARINT: return pb_skip_varint(stream);
272 case PB_WT_64BIT: return pb_read(stream, NULL, 8);
273 case PB_WT_STRING: return pb_skip_string(stream);
274 case PB_WT_32BIT: return pb_read(stream, NULL, 4);
275 default: PB_RETURN_ERROR(stream, "invalid wire_type");
279 /* Read a raw value to buffer, for the purpose of passing it to callback as
280 * a substream. Size is maximum size on call, and actual size on return.
282 static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, uint8_t *buf, size_t *size)
284 size_t max_size = *size;
292 if (*size > max_size) return false;
293 if (!pb_read(stream, buf, 1)) return false;
294 } while (*buf++ & 0x80);
299 return pb_read(stream, buf, 8);
303 return pb_read(stream, buf, 4);
305 default: PB_RETURN_ERROR(stream, "invalid wire_type");
309 /* Decode string length from stream and return a substream with limited length.
310 * Remember to close the substream using pb_close_string_substream().
312 bool checkreturn pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
315 if (!pb_decode_varint32(stream, &size))
318 *substream = *stream;
319 if (substream->bytes_left < size)
320 PB_RETURN_ERROR(stream, "parent stream too short");
322 substream->bytes_left = size;
323 stream->bytes_left -= size;
327 void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream)
329 stream->state = substream->state;
332 stream->errmsg = substream->errmsg;
336 /*************************
337 * Decode a single field *
338 *************************/
340 static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
345 type = iter->pos->type;
346 func = PB_DECODERS[PB_LTYPE(type)];
348 switch (PB_HTYPE(type))
350 case PB_HTYPE_REQUIRED:
351 return func(stream, iter->pos, iter->pData);
353 case PB_HTYPE_OPTIONAL:
354 *(bool*)iter->pSize = true;
355 return func(stream, iter->pos, iter->pData);
357 case PB_HTYPE_REPEATED:
358 if (wire_type == PB_WT_STRING
359 && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
363 pb_size_t *size = (pb_size_t*)iter->pSize;
364 pb_istream_t substream;
365 if (!pb_make_string_substream(stream, &substream))
368 while (substream.bytes_left > 0 && *size < iter->pos->array_size)
370 void *pItem = (uint8_t*)iter->pData + iter->pos->data_size * (*size);
371 if (!func(&substream, iter->pos, pItem))
378 pb_close_string_substream(stream, &substream);
380 if (substream.bytes_left != 0)
381 PB_RETURN_ERROR(stream, "array overflow");
388 pb_size_t *size = (pb_size_t*)iter->pSize;
389 void *pItem = (uint8_t*)iter->pData + iter->pos->data_size * (*size);
390 if (*size >= iter->pos->array_size)
391 PB_RETURN_ERROR(stream, "array overflow");
394 return func(stream, iter->pos, pItem);
398 *(pb_size_t*)iter->pSize = iter->pos->tag;
399 return func(stream, iter->pos, iter->pData);
402 PB_RETURN_ERROR(stream, "invalid field type");
406 #ifdef PB_ENABLE_MALLOC
407 /* Allocate storage for the field and store the pointer at iter->pData.
408 * array_size is the number of entries to reserve in an array.
409 * Zero size is not allowed, use pb_free() for releasing.
411 static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size)
413 void *ptr = *(void**)pData;
415 if (data_size == 0 || array_size == 0)
416 PB_RETURN_ERROR(stream, "invalid size");
418 /* Check for multiplication overflows.
419 * This code avoids the costly division if the sizes are small enough.
420 * Multiplication is safe as long as only half of bits are set
421 * in either multiplicand.
424 const size_t check_limit = (size_t)1 << (sizeof(size_t) * 4);
425 if (data_size >= check_limit || array_size >= check_limit)
427 const size_t size_max = (size_t)-1;
428 if (size_max / array_size < data_size)
430 PB_RETURN_ERROR(stream, "size too large");
435 /* Allocate new or expand previous allocation */
436 /* Note: on failure the old pointer will remain in the structure,
437 * the message must be freed by caller also on error return. */
438 ptr = pb_realloc(ptr, array_size * data_size);
440 PB_RETURN_ERROR(stream, "realloc failed");
442 *(void**)pData = ptr;
446 /* Clear a newly allocated item in case it contains a pointer, or is a submessage. */
447 static void initialize_pointer_field(void *pItem, pb_field_iter_t *iter)
449 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_STRING ||
450 PB_LTYPE(iter->pos->type) == PB_LTYPE_BYTES)
452 *(void**)pItem = NULL;
454 else if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
456 pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, pItem);
461 static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
463 #ifndef PB_ENABLE_MALLOC
464 PB_UNUSED(wire_type);
466 PB_RETURN_ERROR(stream, "no malloc support");
471 type = iter->pos->type;
472 func = PB_DECODERS[PB_LTYPE(type)];
474 switch (PB_HTYPE(type))
476 case PB_HTYPE_REQUIRED:
477 case PB_HTYPE_OPTIONAL:
479 if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE &&
480 *(void**)iter->pData != NULL)
482 /* Duplicate field, have to release the old allocation first. */
483 pb_release_single_field(iter);
486 if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
488 *(pb_size_t*)iter->pSize = iter->pos->tag;
491 if (PB_LTYPE(type) == PB_LTYPE_STRING ||
492 PB_LTYPE(type) == PB_LTYPE_BYTES)
494 return func(stream, iter->pos, iter->pData);
498 if (!allocate_field(stream, iter->pData, iter->pos->data_size, 1))
501 initialize_pointer_field(*(void**)iter->pData, iter);
502 return func(stream, iter->pos, *(void**)iter->pData);
505 case PB_HTYPE_REPEATED:
506 if (wire_type == PB_WT_STRING
507 && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
509 /* Packed array, multiple items come in at once. */
511 pb_size_t *size = (pb_size_t*)iter->pSize;
512 size_t allocated_size = *size;
514 pb_istream_t substream;
516 if (!pb_make_string_substream(stream, &substream))
519 while (substream.bytes_left)
521 if ((size_t)*size + 1 > allocated_size)
523 /* Allocate more storage. This tries to guess the
524 * number of remaining entries. Round the division
526 allocated_size += (substream.bytes_left - 1) / iter->pos->data_size + 1;
528 if (!allocate_field(&substream, iter->pData, iter->pos->data_size, allocated_size))
535 /* Decode the array entry */
536 pItem = *(uint8_t**)iter->pData + iter->pos->data_size * (*size);
537 initialize_pointer_field(pItem, iter);
538 if (!func(&substream, iter->pos, pItem))
544 if (*size == PB_SIZE_MAX)
547 stream->errmsg = "too many array entries";
555 pb_close_string_substream(stream, &substream);
561 /* Normal repeated field, i.e. only one item at a time. */
562 pb_size_t *size = (pb_size_t*)iter->pSize;
565 if (*size == PB_SIZE_MAX)
566 PB_RETURN_ERROR(stream, "too many array entries");
569 if (!allocate_field(stream, iter->pData, iter->pos->data_size, *size))
572 pItem = *(uint8_t**)iter->pData + iter->pos->data_size * (*size - 1);
573 initialize_pointer_field(pItem, iter);
574 return func(stream, iter->pos, pItem);
578 PB_RETURN_ERROR(stream, "invalid field type");
583 static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
585 pb_callback_t *pCallback = (pb_callback_t*)iter->pData;
587 #ifdef PB_OLD_CALLBACK_STYLE
588 void *arg = pCallback->arg;
590 void **arg = &(pCallback->arg);
593 if (pCallback->funcs.decode == NULL)
594 return pb_skip_field(stream, wire_type);
596 if (wire_type == PB_WT_STRING)
598 pb_istream_t substream;
600 if (!pb_make_string_substream(stream, &substream))
605 if (!pCallback->funcs.decode(&substream, iter->pos, arg))
606 PB_RETURN_ERROR(stream, "callback failed");
607 } while (substream.bytes_left);
609 pb_close_string_substream(stream, &substream);
614 /* Copy the single scalar value to stack.
615 * This is required so that we can limit the stream length,
616 * which in turn allows to use same callback for packed and
617 * not-packed fields. */
618 pb_istream_t substream;
620 size_t size = sizeof(buffer);
622 if (!read_raw_value(stream, wire_type, buffer, &size))
624 substream = pb_istream_from_buffer(buffer, size);
626 return pCallback->funcs.decode(&substream, iter->pos, arg);
630 static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
632 #ifdef PB_ENABLE_MALLOC
633 /* When decoding an oneof field, check if there is old data that must be
635 if (PB_HTYPE(iter->pos->type) == PB_HTYPE_ONEOF)
637 if (!pb_release_union_field(stream, iter))
642 switch (PB_ATYPE(iter->pos->type))
644 case PB_ATYPE_STATIC:
645 return decode_static_field(stream, wire_type, iter);
647 case PB_ATYPE_POINTER:
648 return decode_pointer_field(stream, wire_type, iter);
650 case PB_ATYPE_CALLBACK:
651 return decode_callback_field(stream, wire_type, iter);
654 PB_RETURN_ERROR(stream, "invalid field type");
658 static void iter_from_extension(pb_field_iter_t *iter, pb_extension_t *extension)
660 /* Fake a field iterator for the extension field.
661 * It is not actually safe to advance this iterator, but decode_field
662 * will not even try to. */
663 const pb_field_t *field = (const pb_field_t*)extension->type->arg;
664 (void)pb_field_iter_begin(iter, field, extension->dest);
665 iter->pData = extension->dest;
666 iter->pSize = &extension->found;
668 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
670 /* For pointer extensions, the pointer is stored directly
671 * in the extension structure. This avoids having an extra
673 iter->pData = &extension->dest;
677 /* Default handler for extension fields. Expects a pb_field_t structure
678 * in extension->type->arg. */
679 static bool checkreturn default_extension_decoder(pb_istream_t *stream,
680 pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type)
682 const pb_field_t *field = (const pb_field_t*)extension->type->arg;
683 pb_field_iter_t iter;
685 if (field->tag != tag)
688 iter_from_extension(&iter, extension);
689 extension->found = true;
690 return decode_field(stream, wire_type, &iter);
693 /* Try to decode an unknown field as an extension field. Tries each extension
694 * decoder in turn, until one of them handles the field or loop ends. */
695 static bool checkreturn decode_extension(pb_istream_t *stream,
696 uint32_t tag, pb_wire_type_t wire_type, pb_field_iter_t *iter)
698 pb_extension_t *extension = *(pb_extension_t* const *)iter->pData;
699 size_t pos = stream->bytes_left;
701 while (extension != NULL && pos == stream->bytes_left)
704 if (extension->type->decode)
705 status = extension->type->decode(stream, extension, tag, wire_type);
707 status = default_extension_decoder(stream, extension, tag, wire_type);
712 extension = extension->next;
718 /* Step through the iterator until an extension field is found or until all
719 * entries have been checked. There can be only one extension field per
720 * message. Returns false if no extension field is found. */
721 static bool checkreturn find_extension_field(pb_field_iter_t *iter)
723 const pb_field_t *start = iter->pos;
726 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_EXTENSION)
728 (void)pb_field_iter_next(iter);
729 } while (iter->pos != start);
734 /* Initialize message fields to default values, recursively */
735 static void pb_field_set_to_default(pb_field_iter_t *iter)
738 type = iter->pos->type;
740 if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
742 pb_extension_t *ext = *(pb_extension_t* const *)iter->pData;
745 pb_field_iter_t ext_iter;
747 iter_from_extension(&ext_iter, ext);
748 pb_field_set_to_default(&ext_iter);
752 else if (PB_ATYPE(type) == PB_ATYPE_STATIC)
754 bool init_data = true;
755 if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL)
757 /* Set has_field to false. Still initialize the optional field
759 *(bool*)iter->pSize = false;
761 else if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
762 PB_HTYPE(type) == PB_HTYPE_ONEOF)
764 /* REPEATED: Set array count to 0, no need to initialize contents.
765 ONEOF: Set which_field to 0. */
766 *(pb_size_t*)iter->pSize = 0;
772 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
774 /* Initialize submessage to defaults */
775 pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, iter->pData);
777 else if (iter->pos->ptr != NULL)
779 /* Initialize to default value */
780 memcpy(iter->pData, iter->pos->ptr, iter->pos->data_size);
784 /* Initialize to zeros */
785 memset(iter->pData, 0, iter->pos->data_size);
789 else if (PB_ATYPE(type) == PB_ATYPE_POINTER)
791 /* Initialize the pointer to NULL. */
792 *(void**)iter->pData = NULL;
794 /* Initialize array count to 0. */
795 if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
796 PB_HTYPE(type) == PB_HTYPE_ONEOF)
798 *(pb_size_t*)iter->pSize = 0;
801 else if (PB_ATYPE(type) == PB_ATYPE_CALLBACK)
803 /* Don't overwrite callback */
807 static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct)
809 pb_field_iter_t iter;
811 if (!pb_field_iter_begin(&iter, fields, dest_struct))
812 return; /* Empty message type */
816 pb_field_set_to_default(&iter);
817 } while (pb_field_iter_next(&iter));
820 /*********************
821 * Decode all fields *
822 *********************/
824 bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
826 uint8_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 7) / 8] = {0, 0, 0, 0, 0, 0, 0, 0};
827 uint32_t extension_range_start = 0;
828 pb_field_iter_t iter;
830 /* Return value ignored, as empty message types will be correctly handled by
831 * pb_field_iter_find() anyway. */
832 (void)pb_field_iter_begin(&iter, fields, dest_struct);
834 while (stream->bytes_left)
837 pb_wire_type_t wire_type;
840 if (!pb_decode_tag(stream, &wire_type, &tag, &eof))
848 if (!pb_field_iter_find(&iter, tag))
850 /* No match found, check if it matches an extension. */
851 if (tag >= extension_range_start)
853 if (!find_extension_field(&iter))
854 extension_range_start = (uint32_t)-1;
856 extension_range_start = iter.pos->tag;
858 if (tag >= extension_range_start)
860 size_t pos = stream->bytes_left;
862 if (!decode_extension(stream, tag, wire_type, &iter))
865 if (pos != stream->bytes_left)
867 /* The field was handled */
873 /* No match found, skip data */
874 if (!pb_skip_field(stream, wire_type))
879 if (PB_HTYPE(iter.pos->type) == PB_HTYPE_REQUIRED
880 && iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
882 fields_seen[iter.required_field_index >> 3] |= (uint8_t)(1 << (iter.required_field_index & 7));
885 if (!decode_field(stream, wire_type, &iter))
889 /* Check that all required fields were present. */
891 /* First figure out the number of required fields by
892 * seeking to the end of the field array. Usually we
893 * are already close to end after decoding.
895 unsigned req_field_count;
899 req_field_count = iter.required_field_index;
900 last_type = iter.pos->type;
901 } while (pb_field_iter_next(&iter));
903 /* Fixup if last field was also required. */
904 if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED && iter.pos->tag != 0)
907 /* Check the whole bytes */
908 for (i = 0; i < (req_field_count >> 3); i++)
910 if (fields_seen[i] != 0xFF)
911 PB_RETURN_ERROR(stream, "missing required field");
914 /* Check the remaining bits */
915 if (fields_seen[req_field_count >> 3] != (0xFF >> (8 - (req_field_count & 7))))
916 PB_RETURN_ERROR(stream, "missing required field");
922 bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
925 pb_message_set_to_defaults(fields, dest_struct);
926 status = pb_decode_noinit(stream, fields, dest_struct);
928 #ifdef PB_ENABLE_MALLOC
930 pb_release(fields, dest_struct);
936 bool pb_decode_delimited(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
938 pb_istream_t substream;
941 if (!pb_make_string_substream(stream, &substream))
944 status = pb_decode(&substream, fields, dest_struct);
945 pb_close_string_substream(stream, &substream);
949 #ifdef PB_ENABLE_MALLOC
950 /* Given an oneof field, if there has already been a field inside this oneof,
951 * release it before overwriting with a different one. */
952 static bool pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *iter)
954 pb_size_t old_tag = *(pb_size_t*)iter->pSize; /* Previous which_ value */
955 pb_size_t new_tag = iter->pos->tag; /* New which_ value */
958 return true; /* Ok, no old data in union */
960 if (old_tag == new_tag)
961 return true; /* Ok, old data is of same type => merge */
963 /* Release old data. The find can fail if the message struct contains
965 if (!pb_field_iter_find(iter, old_tag))
966 PB_RETURN_ERROR(stream, "invalid union tag");
968 pb_release_single_field(iter);
970 /* Restore iterator to where it should be.
971 * This shouldn't fail unless the pb_field_t structure is corrupted. */
972 if (!pb_field_iter_find(iter, new_tag))
973 PB_RETURN_ERROR(stream, "iterator error");
978 static void pb_release_single_field(const pb_field_iter_t *iter)
981 type = iter->pos->type;
983 if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
985 if (*(pb_size_t*)iter->pSize != iter->pos->tag)
986 return; /* This is not the current field in the union */
989 /* Release anything contained inside an extension or submsg.
990 * This has to be done even if the submsg itself is statically
992 if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
994 /* Release fields from all extensions in the linked list */
995 pb_extension_t *ext = *(pb_extension_t**)iter->pData;
998 pb_field_iter_t ext_iter;
999 iter_from_extension(&ext_iter, ext);
1000 pb_release_single_field(&ext_iter);
1004 else if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)
1006 /* Release fields in submessage or submsg array */
1007 void *pItem = iter->pData;
1008 pb_size_t count = 1;
1010 if (PB_ATYPE(type) == PB_ATYPE_POINTER)
1012 pItem = *(void**)iter->pData;
1015 if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
1017 count = *(pb_size_t*)iter->pSize;
1024 pb_release((const pb_field_t*)iter->pos->ptr, pItem);
1025 pItem = (uint8_t*)pItem + iter->pos->data_size;
1030 if (PB_ATYPE(type) == PB_ATYPE_POINTER)
1032 if (PB_HTYPE(type) == PB_HTYPE_REPEATED &&
1033 (PB_LTYPE(type) == PB_LTYPE_STRING ||
1034 PB_LTYPE(type) == PB_LTYPE_BYTES))
1036 /* Release entries in repeated string or bytes array */
1037 void **pItem = *(void***)iter->pData;
1038 pb_size_t count = *(pb_size_t*)iter->pSize;
1046 if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
1048 /* We are going to release the array, so set the size to 0 */
1049 *(pb_size_t*)iter->pSize = 0;
1052 /* Release main item */
1053 pb_free(*(void**)iter->pData);
1054 *(void**)iter->pData = NULL;
1058 void pb_release(const pb_field_t fields[], void *dest_struct)
1060 pb_field_iter_t iter;
1062 if (!pb_field_iter_begin(&iter, fields, dest_struct))
1063 return; /* Empty message type */
1067 pb_release_single_field(&iter);
1068 } while (pb_field_iter_next(&iter));
1072 /* Field decoders */
1074 bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
1077 if (!pb_decode_varint(stream, &value))
1081 *dest = (int64_t)(~(value >> 1));
1083 *dest = (int64_t)(value >> 1);
1088 bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
1090 #ifdef __BIG_ENDIAN__
1091 uint8_t *bytes = (uint8_t*)dest;
1094 if (!pb_read(stream, lebytes, 4))
1097 bytes[0] = lebytes[3];
1098 bytes[1] = lebytes[2];
1099 bytes[2] = lebytes[1];
1100 bytes[3] = lebytes[0];
1103 return pb_read(stream, (uint8_t*)dest, 4);
1107 bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
1109 #ifdef __BIG_ENDIAN__
1110 uint8_t *bytes = (uint8_t*)dest;
1113 if (!pb_read(stream, lebytes, 8))
1116 bytes[0] = lebytes[7];
1117 bytes[1] = lebytes[6];
1118 bytes[2] = lebytes[5];
1119 bytes[3] = lebytes[4];
1120 bytes[4] = lebytes[3];
1121 bytes[5] = lebytes[2];
1122 bytes[6] = lebytes[1];
1123 bytes[7] = lebytes[0];
1126 return pb_read(stream, (uint8_t*)dest, 8);
1130 static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1135 if (!pb_decode_varint(stream, &value))
1138 /* See issue 97: Google's C++ protobuf allows negative varint values to
1139 * be cast as int32_t, instead of the int64_t that should be used when
1140 * encoding. Previous nanopb versions had a bug in encoding. In order to
1141 * not break decoding of such messages, we cast <=32 bit fields to
1142 * int32_t first to get the sign correct.
1144 if (field->data_size == 8)
1145 svalue = (int64_t)value;
1147 svalue = (int32_t)value;
1149 switch (field->data_size)
1151 case 1: clamped = *(int8_t*)dest = (int8_t)svalue; break;
1152 case 2: clamped = *(int16_t*)dest = (int16_t)svalue; break;
1153 case 4: clamped = *(int32_t*)dest = (int32_t)svalue; break;
1154 case 8: clamped = *(int64_t*)dest = svalue; break;
1155 default: PB_RETURN_ERROR(stream, "invalid data_size");
1158 if (clamped != svalue)
1159 PB_RETURN_ERROR(stream, "integer too large");
1164 static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1166 uint64_t value, clamped;
1167 if (!pb_decode_varint(stream, &value))
1170 switch (field->data_size)
1172 case 1: clamped = *(uint8_t*)dest = (uint8_t)value; break;
1173 case 2: clamped = *(uint16_t*)dest = (uint16_t)value; break;
1174 case 4: clamped = *(uint32_t*)dest = (uint32_t)value; break;
1175 case 8: clamped = *(uint64_t*)dest = value; break;
1176 default: PB_RETURN_ERROR(stream, "invalid data_size");
1179 if (clamped != value)
1180 PB_RETURN_ERROR(stream, "integer too large");
1185 static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1187 int64_t value, clamped;
1188 if (!pb_decode_svarint(stream, &value))
1191 switch (field->data_size)
1193 case 1: clamped = *(int8_t*)dest = (int8_t)value; break;
1194 case 2: clamped = *(int16_t*)dest = (int16_t)value; break;
1195 case 4: clamped = *(int32_t*)dest = (int32_t)value; break;
1196 case 8: clamped = *(int64_t*)dest = value; break;
1197 default: PB_RETURN_ERROR(stream, "invalid data_size");
1200 if (clamped != value)
1201 PB_RETURN_ERROR(stream, "integer too large");
1206 static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest)
1209 return pb_decode_fixed32(stream, dest);
1212 static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest)
1215 return pb_decode_fixed64(stream, dest);
1218 static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest)
1222 pb_bytes_array_t *bdest;
1224 if (!pb_decode_varint32(stream, &size))
1227 if (size > PB_SIZE_MAX)
1228 PB_RETURN_ERROR(stream, "bytes overflow");
1230 alloc_size = PB_BYTES_ARRAY_T_ALLOCSIZE(size);
1231 if (size > alloc_size)
1232 PB_RETURN_ERROR(stream, "size too large");
1234 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
1236 #ifndef PB_ENABLE_MALLOC
1237 PB_RETURN_ERROR(stream, "no malloc support");
1239 if (!allocate_field(stream, dest, alloc_size, 1))
1241 bdest = *(pb_bytes_array_t**)dest;
1246 if (alloc_size > field->data_size)
1247 PB_RETURN_ERROR(stream, "bytes overflow");
1248 bdest = (pb_bytes_array_t*)dest;
1251 bdest->size = (pb_size_t)size;
1252 return pb_read(stream, bdest->bytes, size);
1255 static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest)
1260 if (!pb_decode_varint32(stream, &size))
1263 /* Space for null terminator */
1264 alloc_size = size + 1;
1266 if (alloc_size < size)
1267 PB_RETURN_ERROR(stream, "size too large");
1269 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
1271 #ifndef PB_ENABLE_MALLOC
1272 PB_RETURN_ERROR(stream, "no malloc support");
1274 if (!allocate_field(stream, dest, alloc_size, 1))
1276 dest = *(void**)dest;
1281 if (alloc_size > field->data_size)
1282 PB_RETURN_ERROR(stream, "string overflow");
1285 status = pb_read(stream, (uint8_t*)dest, size);
1286 *((uint8_t*)dest + size) = 0;
1290 static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest)
1293 pb_istream_t substream;
1294 const pb_field_t* submsg_fields = (const pb_field_t*)field->ptr;
1296 if (!pb_make_string_substream(stream, &substream))
1299 if (field->ptr == NULL)
1300 PB_RETURN_ERROR(stream, "invalid field descriptor");
1302 /* New array entries need to be initialized, while required and optional
1303 * submessages have already been initialized in the top-level pb_decode. */
1304 if (PB_HTYPE(field->type) == PB_HTYPE_REPEATED)
1305 status = pb_decode(&substream, submsg_fields, dest);
1307 status = pb_decode_noinit(&substream, submsg_fields, dest);
1309 pb_close_string_substream(stream, &substream);