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"
19 /**************************************
20 * Declarations internal to this file *
21 **************************************/
23 /* Iterator for pb_field_t list */
25 const pb_field_t *start; /* Start of the pb_field_t array */
26 const pb_field_t *pos; /* Current position of the iterator */
27 unsigned field_index; /* Zero-based index of the field. */
28 unsigned required_field_index; /* Zero-based index that counts only the required fields */
29 void *dest_struct; /* Pointer to the destination structure to decode to */
30 void *pData; /* Pointer where to store current field value */
31 void *pSize; /* Pointer where to store the size of current array field */
32 } pb_field_iterator_t;
34 typedef bool (*pb_decoder_t)(pb_istream_t *stream, const pb_field_t *field, void *dest) checkreturn;
36 static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count);
37 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest);
38 static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, uint8_t *buf, size_t *size);
39 static void pb_field_init(pb_field_iterator_t *iter, const pb_field_t *fields, void *dest_struct);
40 static bool pb_field_next(pb_field_iterator_t *iter);
41 static bool checkreturn pb_field_find(pb_field_iterator_t *iter, uint32_t tag);
42 static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter);
43 static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter);
44 static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter);
45 static bool checkreturn default_extension_decoder(pb_istream_t *stream, pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type);
46 static bool checkreturn decode_extension(pb_istream_t *stream, uint32_t tag, pb_wire_type_t wire_type, pb_field_iterator_t *iter);
47 static bool checkreturn find_extension_field(pb_field_iterator_t *iter);
48 static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct);
49 static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest);
50 static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
51 static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
52 static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
53 static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest);
54 static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
55 static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
56 static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest);
57 static bool checkreturn pb_skip_varint(pb_istream_t *stream);
58 static bool checkreturn pb_skip_string(pb_istream_t *stream);
60 /* --- Function pointers to field decoders ---
61 * Order in the array must match pb_action_t LTYPE numbering.
63 static const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT] = {
76 /*******************************
77 * pb_istream_t implementation *
78 *******************************/
80 static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count)
82 uint8_t *source = (uint8_t*)stream->state;
83 stream->state = source + count;
94 bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
96 #ifndef PB_BUFFER_ONLY
97 if (buf == NULL && stream->callback != buf_read)
99 /* Skip input bytes */
103 if (!pb_read(stream, tmp, 16))
109 return pb_read(stream, tmp, count);
113 if (stream->bytes_left < count)
114 PB_RETURN_ERROR(stream, "end-of-stream");
116 #ifndef PB_BUFFER_ONLY
117 if (!stream->callback(stream, buf, count))
118 PB_RETURN_ERROR(stream, "io error");
120 if (!buf_read(stream, buf, count))
124 stream->bytes_left -= count;
128 /* Read a single byte from input stream. buf may not be NULL.
129 * This is an optimization for the varint decoding. */
130 static bool checkreturn pb_readbyte(pb_istream_t *stream, uint8_t *buf)
132 if (stream->bytes_left == 0)
133 PB_RETURN_ERROR(stream, "end-of-stream");
135 #ifndef PB_BUFFER_ONLY
136 if (!stream->callback(stream, buf, 1))
137 PB_RETURN_ERROR(stream, "io error");
139 *buf = *(uint8_t*)stream->state;
140 stream->state = (uint8_t*)stream->state + 1;
143 stream->bytes_left--;
148 pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize)
151 #ifdef PB_BUFFER_ONLY
152 stream.callback = NULL;
154 stream.callback = &buf_read;
157 stream.bytes_left = bufsize;
159 stream.errmsg = NULL;
164 /********************
166 ********************/
168 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
173 if (!pb_readbyte(stream, &byte))
176 if ((byte & 0x80) == 0)
178 /* Quick case, 1 byte value */
185 result = byte & 0x7F;
190 PB_RETURN_ERROR(stream, "varint overflow");
192 if (!pb_readbyte(stream, &byte))
195 result |= (uint32_t)(byte & 0x7F) << bitpos;
196 bitpos = (uint8_t)(bitpos + 7);
197 } while (byte & 0x80);
204 bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
213 PB_RETURN_ERROR(stream, "varint overflow");
215 if (!pb_readbyte(stream, &byte))
218 result |= (uint64_t)(byte & 0x7F) << bitpos;
219 bitpos = (uint8_t)(bitpos + 7);
220 } while (byte & 0x80);
226 bool checkreturn pb_skip_varint(pb_istream_t *stream)
231 if (!pb_read(stream, &byte, 1))
233 } while (byte & 0x80);
237 bool checkreturn pb_skip_string(pb_istream_t *stream)
240 if (!pb_decode_varint32(stream, &length))
243 return pb_read(stream, NULL, length);
246 bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof)
250 *wire_type = (pb_wire_type_t) 0;
253 if (!pb_decode_varint32(stream, &temp))
255 if (stream->bytes_left == 0)
263 *eof = true; /* Special feature: allow 0-terminated messages. */
268 *wire_type = (pb_wire_type_t)(temp & 7);
272 bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
276 case PB_WT_VARINT: return pb_skip_varint(stream);
277 case PB_WT_64BIT: return pb_read(stream, NULL, 8);
278 case PB_WT_STRING: return pb_skip_string(stream);
279 case PB_WT_32BIT: return pb_read(stream, NULL, 4);
280 default: PB_RETURN_ERROR(stream, "invalid wire_type");
284 /* Read a raw value to buffer, for the purpose of passing it to callback as
285 * a substream. Size is maximum size on call, and actual size on return.
287 static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, uint8_t *buf, size_t *size)
289 size_t max_size = *size;
297 if (*size > max_size) return false;
298 if (!pb_read(stream, buf, 1)) return false;
299 } while (*buf++ & 0x80);
304 return pb_read(stream, buf, 8);
308 return pb_read(stream, buf, 4);
310 default: PB_RETURN_ERROR(stream, "invalid wire_type");
314 /* Decode string length from stream and return a substream with limited length.
315 * Remember to close the substream using pb_close_string_substream().
317 bool checkreturn pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
320 if (!pb_decode_varint32(stream, &size))
323 *substream = *stream;
324 if (substream->bytes_left < size)
325 PB_RETURN_ERROR(stream, "parent stream too short");
327 substream->bytes_left = size;
328 stream->bytes_left -= size;
332 void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream)
334 stream->state = substream->state;
337 stream->errmsg = substream->errmsg;
341 static void pb_field_init(pb_field_iterator_t *iter, const pb_field_t *fields, void *dest_struct)
343 iter->start = iter->pos = fields;
344 iter->field_index = 0;
345 iter->required_field_index = 0;
346 iter->pData = (char*)dest_struct + iter->pos->data_offset;
347 iter->pSize = (char*)iter->pData + iter->pos->size_offset;
348 iter->dest_struct = dest_struct;
351 static bool pb_field_next(pb_field_iterator_t *iter)
353 bool notwrapped = true;
354 size_t prev_size = iter->pos->data_size;
356 if (PB_ATYPE(iter->pos->type) == PB_ATYPE_STATIC &&
357 PB_HTYPE(iter->pos->type) == PB_HTYPE_REPEATED)
359 prev_size *= iter->pos->array_size;
361 else if (PB_ATYPE(iter->pos->type) == PB_ATYPE_POINTER)
363 prev_size = sizeof(void*);
366 if (iter->pos->tag == 0)
367 return false; /* Only happens with empty message types */
369 if (PB_HTYPE(iter->pos->type) == PB_HTYPE_REQUIRED)
370 iter->required_field_index++;
374 if (iter->pos->tag == 0)
376 iter->pos = iter->start;
377 iter->field_index = 0;
378 iter->required_field_index = 0;
379 iter->pData = iter->dest_struct;
384 iter->pData = (char*)iter->pData + prev_size + iter->pos->data_offset;
385 iter->pSize = (char*)iter->pData + iter->pos->size_offset;
389 static bool checkreturn pb_field_find(pb_field_iterator_t *iter, uint32_t tag)
391 unsigned start = iter->field_index;
394 if (iter->pos->tag == tag &&
395 PB_LTYPE(iter->pos->type) != PB_LTYPE_EXTENSION)
399 (void)pb_field_next(iter);
400 } while (iter->field_index != start);
405 /*************************
406 * Decode a single field *
407 *************************/
409 static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter)
414 type = iter->pos->type;
415 func = PB_DECODERS[PB_LTYPE(type)];
417 switch (PB_HTYPE(type))
419 case PB_HTYPE_REQUIRED:
420 return func(stream, iter->pos, iter->pData);
422 case PB_HTYPE_OPTIONAL:
423 *(bool*)iter->pSize = true;
424 return func(stream, iter->pos, iter->pData);
426 case PB_HTYPE_REPEATED:
427 if (wire_type == PB_WT_STRING
428 && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
432 size_t *size = (size_t*)iter->pSize;
433 pb_istream_t substream;
434 if (!pb_make_string_substream(stream, &substream))
437 while (substream.bytes_left > 0 && *size < iter->pos->array_size)
439 void *pItem = (uint8_t*)iter->pData + iter->pos->data_size * (*size);
440 if (!func(&substream, iter->pos, pItem))
447 pb_close_string_substream(stream, &substream);
449 if (substream.bytes_left != 0)
450 PB_RETURN_ERROR(stream, "array overflow");
457 size_t *size = (size_t*)iter->pSize;
458 void *pItem = (uint8_t*)iter->pData + iter->pos->data_size * (*size);
459 if (*size >= iter->pos->array_size)
460 PB_RETURN_ERROR(stream, "array overflow");
463 return func(stream, iter->pos, pItem);
467 PB_RETURN_ERROR(stream, "invalid field type");
471 #ifdef PB_ENABLE_MALLOC
472 /* Allocate storage for the field and store the pointer at iter->pData.
473 * array_size is the number of entries to reserve in an array. */
474 static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size)
476 void *ptr = *(void**)pData;
477 size_t size = array_size * data_size;
479 /* Allocate new or expand previous allocation */
480 /* Note: on failure the old pointer will remain in the structure,
481 * the message must be freed by caller also on error return. */
482 ptr = pb_realloc(ptr, size);
484 PB_RETURN_ERROR(stream, "realloc failed");
486 *(void**)pData = ptr;
490 /* Clear a newly allocated item in case it contains a pointer, or is a submessage. */
491 static void initialize_pointer_field(void *pItem, pb_field_iterator_t *iter)
493 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_STRING ||
494 PB_LTYPE(iter->pos->type) == PB_LTYPE_BYTES)
496 *(void**)pItem = NULL;
498 else if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
500 pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, pItem);
505 static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter)
507 #ifndef PB_ENABLE_MALLOC
510 PB_RETURN_ERROR(stream, "no malloc support");
515 type = iter->pos->type;
516 func = PB_DECODERS[PB_LTYPE(type)];
518 switch (PB_HTYPE(type))
520 case PB_HTYPE_REQUIRED:
521 case PB_HTYPE_OPTIONAL:
522 if (PB_LTYPE(type) == PB_LTYPE_STRING ||
523 PB_LTYPE(type) == PB_LTYPE_BYTES)
525 return func(stream, iter->pos, iter->pData);
529 if (!allocate_field(stream, iter->pData, iter->pos->data_size, 1))
532 initialize_pointer_field(*(void**)iter->pData, iter);
533 return func(stream, iter->pos, *(void**)iter->pData);
536 case PB_HTYPE_REPEATED:
537 if (wire_type == PB_WT_STRING
538 && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
540 /* Packed array, multiple items come in at once. */
542 size_t *size = (size_t*)iter->pSize;
543 size_t allocated_size = *size;
545 pb_istream_t substream;
547 if (!pb_make_string_substream(stream, &substream))
550 while (substream.bytes_left)
552 if (*size + 1 > allocated_size)
554 /* Allocate more storage. This tries to guess the
555 * number of remaining entries. Round the division
557 allocated_size += (substream.bytes_left - 1) / iter->pos->data_size + 1;
559 if (!allocate_field(&substream, iter->pData, iter->pos->data_size, allocated_size))
566 /* Decode the array entry */
567 pItem = *(uint8_t**)iter->pData + iter->pos->data_size * (*size);
568 initialize_pointer_field(pItem, iter);
569 if (!func(&substream, iter->pos, pItem))
576 pb_close_string_substream(stream, &substream);
582 /* Normal repeated field, i.e. only one item at a time. */
583 size_t *size = (size_t*)iter->pSize;
587 if (!allocate_field(stream, iter->pData, iter->pos->data_size, *size))
590 pItem = *(uint8_t**)iter->pData + iter->pos->data_size * (*size - 1);
591 initialize_pointer_field(pItem, iter);
592 return func(stream, iter->pos, pItem);
596 PB_RETURN_ERROR(stream, "invalid field type");
601 static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter)
603 pb_callback_t *pCallback = (pb_callback_t*)iter->pData;
605 #ifdef PB_OLD_CALLBACK_STYLE
606 void *arg = pCallback->arg;
608 void **arg = &(pCallback->arg);
611 if (pCallback->funcs.decode == NULL)
612 return pb_skip_field(stream, wire_type);
614 if (wire_type == PB_WT_STRING)
616 pb_istream_t substream;
618 if (!pb_make_string_substream(stream, &substream))
623 if (!pCallback->funcs.decode(&substream, iter->pos, arg))
624 PB_RETURN_ERROR(stream, "callback failed");
625 } while (substream.bytes_left);
627 pb_close_string_substream(stream, &substream);
632 /* Copy the single scalar value to stack.
633 * This is required so that we can limit the stream length,
634 * which in turn allows to use same callback for packed and
635 * not-packed fields. */
636 pb_istream_t substream;
638 size_t size = sizeof(buffer);
640 if (!read_raw_value(stream, wire_type, buffer, &size))
642 substream = pb_istream_from_buffer(buffer, size);
644 return pCallback->funcs.decode(&substream, iter->pos, arg);
648 static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter)
650 switch (PB_ATYPE(iter->pos->type))
652 case PB_ATYPE_STATIC:
653 return decode_static_field(stream, wire_type, iter);
655 case PB_ATYPE_POINTER:
656 return decode_pointer_field(stream, wire_type, iter);
658 case PB_ATYPE_CALLBACK:
659 return decode_callback_field(stream, wire_type, iter);
662 PB_RETURN_ERROR(stream, "invalid field type");
666 /* Default handler for extension fields. Expects a pb_field_t structure
667 * in extension->type->arg. */
668 static bool checkreturn default_extension_decoder(pb_istream_t *stream,
669 pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type)
671 const pb_field_t *field = (const pb_field_t*)extension->type->arg;
672 pb_field_iterator_t iter;
674 if (field->tag != tag)
679 iter.field_index = 0;
680 iter.required_field_index = 0;
681 iter.dest_struct = extension->dest;
682 iter.pData = extension->dest;
683 iter.pSize = &extension->found;
685 return decode_field(stream, wire_type, &iter);
688 /* Try to decode an unknown field as an extension field. Tries each extension
689 * decoder in turn, until one of them handles the field or loop ends. */
690 static bool checkreturn decode_extension(pb_istream_t *stream,
691 uint32_t tag, pb_wire_type_t wire_type, pb_field_iterator_t *iter)
693 pb_extension_t *extension = *(pb_extension_t* const *)iter->pData;
694 size_t pos = stream->bytes_left;
696 while (extension != NULL && pos == stream->bytes_left)
699 if (extension->type->decode)
700 status = extension->type->decode(stream, extension, tag, wire_type);
702 status = default_extension_decoder(stream, extension, tag, wire_type);
707 extension = extension->next;
713 /* Step through the iterator until an extension field is found or until all
714 * entries have been checked. There can be only one extension field per
715 * message. Returns false if no extension field is found. */
716 static bool checkreturn find_extension_field(pb_field_iterator_t *iter)
718 unsigned start = iter->field_index;
721 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_EXTENSION)
723 (void)pb_field_next(iter);
724 } while (iter->field_index != start);
729 /* Initialize message fields to default values, recursively */
730 static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct)
732 pb_field_iterator_t iter;
733 pb_field_init(&iter, fields, dest_struct);
738 type = iter.pos->type;
740 /* Avoid crash on empty message types (zero fields) */
741 if (iter.pos->tag == 0)
744 if (PB_ATYPE(type) == PB_ATYPE_STATIC)
746 if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL)
748 /* Set has_field to false. Still initialize the optional field
750 *(bool*)iter.pSize = false;
752 else if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
754 /* Set array count to 0, no need to initialize contents. */
755 *(size_t*)iter.pSize = 0;
759 if (PB_LTYPE(iter.pos->type) == PB_LTYPE_SUBMESSAGE)
761 /* Initialize submessage to defaults */
762 pb_message_set_to_defaults((const pb_field_t *) iter.pos->ptr, iter.pData);
764 else if (iter.pos->ptr != NULL)
766 /* Initialize to default value */
767 memcpy(iter.pData, iter.pos->ptr, iter.pos->data_size);
771 /* Initialize to zeros */
772 memset(iter.pData, 0, iter.pos->data_size);
775 else if (PB_ATYPE(type) == PB_ATYPE_POINTER)
777 /* Initialize the pointer to NULL. */
778 *(void**)iter.pData = NULL;
780 /* Initialize array count to 0. */
781 if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
783 *(size_t*)iter.pSize = 0;
786 else if (PB_ATYPE(type) == PB_ATYPE_CALLBACK)
788 /* Don't overwrite callback */
790 } while (pb_field_next(&iter));
793 /*********************
794 * Decode all fields *
795 *********************/
797 bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
799 uint8_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 7) / 8] = {0, 0, 0, 0, 0, 0, 0, 0};
800 uint32_t extension_range_start = 0;
801 pb_field_iterator_t iter;
803 pb_field_init(&iter, fields, dest_struct);
805 while (stream->bytes_left)
808 pb_wire_type_t wire_type;
811 if (!pb_decode_tag(stream, &wire_type, &tag, &eof))
819 if (!pb_field_find(&iter, tag))
821 /* No match found, check if it matches an extension. */
822 if (tag >= extension_range_start)
824 if (!find_extension_field(&iter))
825 extension_range_start = (uint32_t)-1;
827 extension_range_start = iter.pos->tag;
829 if (tag >= extension_range_start)
831 size_t pos = stream->bytes_left;
833 if (!decode_extension(stream, tag, wire_type, &iter))
836 if (pos != stream->bytes_left)
838 /* The field was handled */
844 /* No match found, skip data */
845 if (!pb_skip_field(stream, wire_type))
850 if (PB_HTYPE(iter.pos->type) == PB_HTYPE_REQUIRED
851 && iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
853 fields_seen[iter.required_field_index >> 3] |= (uint8_t)(1 << (iter.required_field_index & 7));
856 if (!decode_field(stream, wire_type, &iter))
860 /* Check that all required fields were present. */
862 /* First figure out the number of required fields by
863 * seeking to the end of the field array. Usually we
864 * are already close to end after decoding.
866 unsigned req_field_count;
870 req_field_count = iter.required_field_index;
871 last_type = iter.pos->type;
872 } while (pb_field_next(&iter));
874 /* Fixup if last field was also required. */
875 if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED && iter.pos->tag != 0)
878 /* Check the whole bytes */
879 for (i = 0; i < (req_field_count >> 3); i++)
881 if (fields_seen[i] != 0xFF)
882 PB_RETURN_ERROR(stream, "missing required field");
885 /* Check the remaining bits */
886 if (fields_seen[req_field_count >> 3] != (0xFF >> (8 - (req_field_count & 7))))
887 PB_RETURN_ERROR(stream, "missing required field");
893 bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
896 pb_message_set_to_defaults(fields, dest_struct);
897 status = pb_decode_noinit(stream, fields, dest_struct);
899 #ifdef PB_ENABLE_MALLOC
901 pb_release(fields, dest_struct);
907 bool pb_decode_delimited(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
909 pb_istream_t substream;
912 if (!pb_make_string_substream(stream, &substream))
915 status = pb_decode(&substream, fields, dest_struct);
916 pb_close_string_substream(stream, &substream);
920 #ifdef PB_ENABLE_MALLOC
921 void pb_release(const pb_field_t fields[], void *dest_struct)
923 pb_field_iterator_t iter;
924 pb_field_init(&iter, fields, dest_struct);
929 type = iter.pos->type;
931 /* Avoid crash on empty message types (zero fields) */
932 if (iter.pos->tag == 0)
935 if (PB_ATYPE(type) == PB_ATYPE_POINTER)
937 if (PB_HTYPE(type) == PB_HTYPE_REPEATED &&
938 (PB_LTYPE(type) == PB_LTYPE_STRING ||
939 PB_LTYPE(type) == PB_LTYPE_BYTES))
941 /* Release entries in repeated string or bytes array */
942 void **pItem = *(void***)iter.pData;
943 size_t count = *(size_t*)iter.pSize;
950 else if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)
952 /* Release fields in submessages */
953 void *pItem = *(void**)iter.pData;
954 size_t count = (pItem ? 1 : 0);
956 if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
958 count = *(size_t*)iter.pSize;
963 pb_release((const pb_field_t*)iter.pos->ptr, pItem);
964 pItem = (uint8_t*)pItem + iter.pos->data_size;
968 /* Release main item */
969 pb_free(*(void**)iter.pData);
970 *(void**)iter.pData = NULL;
972 } while (pb_field_next(&iter));
978 bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
981 if (!pb_decode_varint(stream, &value))
985 *dest = (int64_t)(~(value >> 1));
987 *dest = (int64_t)(value >> 1);
992 bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
994 #ifdef __BIG_ENDIAN__
995 uint8_t *bytes = (uint8_t*)dest;
998 if (!pb_read(stream, lebytes, 4))
1001 bytes[0] = lebytes[3];
1002 bytes[1] = lebytes[2];
1003 bytes[2] = lebytes[1];
1004 bytes[3] = lebytes[0];
1007 return pb_read(stream, (uint8_t*)dest, 4);
1011 bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
1013 #ifdef __BIG_ENDIAN__
1014 uint8_t *bytes = (uint8_t*)dest;
1017 if (!pb_read(stream, lebytes, 8))
1020 bytes[0] = lebytes[7];
1021 bytes[1] = lebytes[6];
1022 bytes[2] = lebytes[5];
1023 bytes[3] = lebytes[4];
1024 bytes[4] = lebytes[3];
1025 bytes[5] = lebytes[2];
1026 bytes[6] = lebytes[1];
1027 bytes[7] = lebytes[0];
1030 return pb_read(stream, (uint8_t*)dest, 8);
1034 static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1037 if (!pb_decode_varint(stream, &value))
1040 switch (field->data_size)
1042 case 1: *(int8_t*)dest = (int8_t)value; break;
1043 case 2: *(int16_t*)dest = (int16_t)value; break;
1044 case 4: *(int32_t*)dest = (int32_t)value; break;
1045 case 8: *(int64_t*)dest = (int64_t)value; break;
1046 default: PB_RETURN_ERROR(stream, "invalid data_size");
1052 static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1055 if (!pb_decode_varint(stream, &value))
1058 switch (field->data_size)
1060 case 4: *(uint32_t*)dest = (uint32_t)value; break;
1061 case 8: *(uint64_t*)dest = value; break;
1062 default: PB_RETURN_ERROR(stream, "invalid data_size");
1068 static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1071 if (!pb_decode_svarint(stream, &value))
1074 switch (field->data_size)
1076 case 4: *(int32_t*)dest = (int32_t)value; break;
1077 case 8: *(int64_t*)dest = value; break;
1078 default: PB_RETURN_ERROR(stream, "invalid data_size");
1084 static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest)
1087 return pb_decode_fixed32(stream, dest);
1090 static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest)
1093 return pb_decode_fixed64(stream, dest);
1096 static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest)
1099 pb_bytes_array_t *bdest;
1101 if (!pb_decode_varint32(stream, &size))
1104 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
1106 #ifndef PB_ENABLE_MALLOC
1107 PB_RETURN_ERROR(stream, "no malloc support");
1109 if (!allocate_field(stream, dest, PB_BYTES_ARRAY_T_ALLOCSIZE(size), 1))
1111 bdest = *(pb_bytes_array_t**)dest;
1116 if (PB_BYTES_ARRAY_T_ALLOCSIZE(size) > field->data_size)
1117 PB_RETURN_ERROR(stream, "bytes overflow");
1118 bdest = (pb_bytes_array_t*)dest;
1122 return pb_read(stream, bdest->bytes, size);
1125 static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest)
1130 if (!pb_decode_varint32(stream, &size))
1133 /* Space for null terminator */
1134 alloc_size = size + 1;
1136 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
1138 #ifndef PB_ENABLE_MALLOC
1139 PB_RETURN_ERROR(stream, "no malloc support");
1141 if (!allocate_field(stream, dest, alloc_size, 1))
1143 dest = *(void**)dest;
1148 if (alloc_size > field->data_size)
1149 PB_RETURN_ERROR(stream, "string overflow");
1152 status = pb_read(stream, (uint8_t*)dest, size);
1153 *((uint8_t*)dest + size) = 0;
1157 static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest)
1160 pb_istream_t substream;
1161 const pb_field_t* submsg_fields = (const pb_field_t*)field->ptr;
1163 if (!pb_make_string_substream(stream, &substream))
1166 if (field->ptr == NULL)
1167 PB_RETURN_ERROR(stream, "invalid field descriptor");
1169 /* New array entries need to be initialized, while required and optional
1170 * submessages have already been initialized in the top-level pb_decode. */
1171 if (PB_HTYPE(field->type) == PB_HTYPE_REPEATED)
1172 status = pb_decode(&substream, submsg_fields, dest);
1174 status = pb_decode_noinit(&substream, submsg_fields, dest);
1176 pb_close_string_substream(stream, &substream);