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, pb_byte_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, pb_byte_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] = {
68 NULL, /* extensions */
69 &pb_dec_bytes /* PB_LTYPE_FIXED_LENGTH_BYTES */
72 /*******************************
73 * pb_istream_t implementation *
74 *******************************/
76 static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
78 const pb_byte_t *source = (const pb_byte_t*)stream->state;
79 stream->state = (pb_byte_t*)stream->state + count;
90 bool checkreturn pb_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
92 #ifndef PB_BUFFER_ONLY
93 if (buf == NULL && stream->callback != buf_read)
95 /* Skip input bytes */
99 if (!pb_read(stream, tmp, 16))
105 return pb_read(stream, tmp, count);
109 if (stream->bytes_left < count)
110 PB_RETURN_ERROR(stream, "end-of-stream");
112 #ifndef PB_BUFFER_ONLY
113 if (!stream->callback(stream, buf, count))
114 PB_RETURN_ERROR(stream, "io error");
116 if (!buf_read(stream, buf, count))
120 stream->bytes_left -= count;
124 /* Read a single byte from input stream. buf may not be NULL.
125 * This is an optimization for the varint decoding. */
126 static bool checkreturn pb_readbyte(pb_istream_t *stream, pb_byte_t *buf)
128 if (stream->bytes_left == 0)
129 PB_RETURN_ERROR(stream, "end-of-stream");
131 #ifndef PB_BUFFER_ONLY
132 if (!stream->callback(stream, buf, 1))
133 PB_RETURN_ERROR(stream, "io error");
135 *buf = *(const pb_byte_t*)stream->state;
136 stream->state = (pb_byte_t*)stream->state + 1;
139 stream->bytes_left--;
144 pb_istream_t pb_istream_from_buffer(const pb_byte_t *buf, size_t bufsize)
147 /* Cast away the const from buf without a compiler error. We are
148 * careful to use it only in a const manner in the callbacks.
154 #ifdef PB_BUFFER_ONLY
155 stream.callback = NULL;
157 stream.callback = &buf_read;
160 stream.state = state.state;
161 stream.bytes_left = bufsize;
163 stream.errmsg = NULL;
168 /********************
170 ********************/
172 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
177 if (!pb_readbyte(stream, &byte))
180 if ((byte & 0x80) == 0)
182 /* Quick case, 1 byte value */
188 uint_fast8_t bitpos = 7;
189 result = byte & 0x7F;
194 PB_RETURN_ERROR(stream, "varint overflow");
196 if (!pb_readbyte(stream, &byte))
199 result |= (uint32_t)(byte & 0x7F) << bitpos;
200 bitpos = (uint_fast8_t)(bitpos + 7);
201 } while (byte & 0x80);
208 bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
211 uint_fast8_t bitpos = 0;
217 PB_RETURN_ERROR(stream, "varint overflow");
219 if (!pb_readbyte(stream, &byte))
222 result |= (uint64_t)(byte & 0x7F) << bitpos;
223 bitpos = (uint_fast8_t)(bitpos + 7);
224 } while (byte & 0x80);
230 bool checkreturn pb_skip_varint(pb_istream_t *stream)
235 if (!pb_read(stream, &byte, 1))
237 } while (byte & 0x80);
241 bool checkreturn pb_skip_string(pb_istream_t *stream)
244 if (!pb_decode_varint32(stream, &length))
247 return pb_read(stream, NULL, length);
250 bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof)
254 *wire_type = (pb_wire_type_t) 0;
257 if (!pb_decode_varint32(stream, &temp))
259 if (stream->bytes_left == 0)
267 *eof = true; /* Special feature: allow 0-terminated messages. */
272 *wire_type = (pb_wire_type_t)(temp & 7);
276 bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
280 case PB_WT_VARINT: return pb_skip_varint(stream);
281 case PB_WT_64BIT: return pb_read(stream, NULL, 8);
282 case PB_WT_STRING: return pb_skip_string(stream);
283 case PB_WT_32BIT: return pb_read(stream, NULL, 4);
284 default: PB_RETURN_ERROR(stream, "invalid wire_type");
288 /* Read a raw value to buffer, for the purpose of passing it to callback as
289 * a substream. Size is maximum size on call, and actual size on return.
291 static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size)
293 size_t max_size = *size;
301 if (*size > max_size) return false;
302 if (!pb_read(stream, buf, 1)) return false;
303 } while (*buf++ & 0x80);
308 return pb_read(stream, buf, 8);
312 return pb_read(stream, buf, 4);
314 default: PB_RETURN_ERROR(stream, "invalid wire_type");
318 /* Decode string length from stream and return a substream with limited length.
319 * Remember to close the substream using pb_close_string_substream().
321 bool checkreturn pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
324 if (!pb_decode_varint32(stream, &size))
327 *substream = *stream;
328 if (substream->bytes_left < size)
329 PB_RETURN_ERROR(stream, "parent stream too short");
331 substream->bytes_left = size;
332 stream->bytes_left -= size;
336 void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream)
338 stream->state = substream->state;
341 stream->errmsg = substream->errmsg;
345 /*************************
346 * Decode a single field *
347 *************************/
349 static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
354 type = iter->pos->type;
355 func = PB_DECODERS[PB_LTYPE(type)];
357 switch (PB_HTYPE(type))
359 case PB_HTYPE_REQUIRED:
360 return func(stream, iter->pos, iter->pData);
362 case PB_HTYPE_OPTIONAL:
363 *(bool*)iter->pSize = true;
364 return func(stream, iter->pos, iter->pData);
366 case PB_HTYPE_REPEATED:
367 if (wire_type == PB_WT_STRING
368 && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
372 pb_size_t *size = (pb_size_t*)iter->pSize;
373 pb_istream_t substream;
374 if (!pb_make_string_substream(stream, &substream))
377 while (substream.bytes_left > 0 && *size < iter->pos->array_size)
379 void *pItem = (char*)iter->pData + iter->pos->data_size * (*size);
380 if (!func(&substream, iter->pos, pItem))
387 pb_close_string_substream(stream, &substream);
389 if (substream.bytes_left != 0)
390 PB_RETURN_ERROR(stream, "array overflow");
397 pb_size_t *size = (pb_size_t*)iter->pSize;
398 void *pItem = (char*)iter->pData + iter->pos->data_size * (*size);
399 if (*size >= iter->pos->array_size)
400 PB_RETURN_ERROR(stream, "array overflow");
403 return func(stream, iter->pos, pItem);
407 *(pb_size_t*)iter->pSize = iter->pos->tag;
408 if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)
410 /* We memset to zero so that any callbacks are set to NULL.
411 * Then set any default values. */
412 memset(iter->pData, 0, iter->pos->data_size);
413 pb_message_set_to_defaults((const pb_field_t*)iter->pos->ptr, iter->pData);
415 return func(stream, iter->pos, iter->pData);
418 PB_RETURN_ERROR(stream, "invalid field type");
422 #ifdef PB_ENABLE_MALLOC
423 /* Allocate storage for the field and store the pointer at iter->pData.
424 * array_size is the number of entries to reserve in an array.
425 * Zero size is not allowed, use pb_free() for releasing.
427 static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size)
429 void *ptr = *(void**)pData;
431 if (data_size == 0 || array_size == 0)
432 PB_RETURN_ERROR(stream, "invalid size");
434 /* Check for multiplication overflows.
435 * This code avoids the costly division if the sizes are small enough.
436 * Multiplication is safe as long as only half of bits are set
437 * in either multiplicand.
440 const size_t check_limit = (size_t)1 << (sizeof(size_t) * 4);
441 if (data_size >= check_limit || array_size >= check_limit)
443 const size_t size_max = (size_t)-1;
444 if (size_max / array_size < data_size)
446 PB_RETURN_ERROR(stream, "size too large");
451 /* Allocate new or expand previous allocation */
452 /* Note: on failure the old pointer will remain in the structure,
453 * the message must be freed by caller also on error return. */
454 ptr = pb_realloc(ptr, array_size * data_size);
456 PB_RETURN_ERROR(stream, "realloc failed");
458 *(void**)pData = ptr;
462 /* Clear a newly allocated item in case it contains a pointer, or is a submessage. */
463 static void initialize_pointer_field(void *pItem, pb_field_iter_t *iter)
465 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_STRING ||
466 PB_LTYPE(iter->pos->type) == PB_LTYPE_BYTES)
468 *(void**)pItem = NULL;
470 else if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
472 pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, pItem);
477 static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
479 #ifndef PB_ENABLE_MALLOC
480 PB_UNUSED(wire_type);
482 PB_RETURN_ERROR(stream, "no malloc support");
487 type = iter->pos->type;
488 func = PB_DECODERS[PB_LTYPE(type)];
490 switch (PB_HTYPE(type))
492 case PB_HTYPE_REQUIRED:
493 case PB_HTYPE_OPTIONAL:
495 if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE &&
496 *(void**)iter->pData != NULL)
498 /* Duplicate field, have to release the old allocation first. */
499 pb_release_single_field(iter);
502 if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
504 *(pb_size_t*)iter->pSize = iter->pos->tag;
507 if (PB_LTYPE(type) == PB_LTYPE_STRING ||
508 PB_LTYPE(type) == PB_LTYPE_BYTES)
510 return func(stream, iter->pos, iter->pData);
514 if (!allocate_field(stream, iter->pData, iter->pos->data_size, 1))
517 initialize_pointer_field(*(void**)iter->pData, iter);
518 return func(stream, iter->pos, *(void**)iter->pData);
521 case PB_HTYPE_REPEATED:
522 if (wire_type == PB_WT_STRING
523 && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
525 /* Packed array, multiple items come in at once. */
527 pb_size_t *size = (pb_size_t*)iter->pSize;
528 size_t allocated_size = *size;
530 pb_istream_t substream;
532 if (!pb_make_string_substream(stream, &substream))
535 while (substream.bytes_left)
537 if ((size_t)*size + 1 > allocated_size)
539 /* Allocate more storage. This tries to guess the
540 * number of remaining entries. Round the division
542 allocated_size += (substream.bytes_left - 1) / iter->pos->data_size + 1;
544 if (!allocate_field(&substream, iter->pData, iter->pos->data_size, allocated_size))
551 /* Decode the array entry */
552 pItem = *(char**)iter->pData + iter->pos->data_size * (*size);
553 initialize_pointer_field(pItem, iter);
554 if (!func(&substream, iter->pos, pItem))
560 if (*size == PB_SIZE_MAX)
563 stream->errmsg = "too many array entries";
571 pb_close_string_substream(stream, &substream);
577 /* Normal repeated field, i.e. only one item at a time. */
578 pb_size_t *size = (pb_size_t*)iter->pSize;
581 if (*size == PB_SIZE_MAX)
582 PB_RETURN_ERROR(stream, "too many array entries");
585 if (!allocate_field(stream, iter->pData, iter->pos->data_size, *size))
588 pItem = *(char**)iter->pData + iter->pos->data_size * (*size - 1);
589 initialize_pointer_field(pItem, iter);
590 return func(stream, iter->pos, pItem);
594 PB_RETURN_ERROR(stream, "invalid field type");
599 static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
601 pb_callback_t *pCallback = (pb_callback_t*)iter->pData;
603 #ifdef PB_OLD_CALLBACK_STYLE
604 void *arg = pCallback->arg;
606 void **arg = &(pCallback->arg);
609 if (pCallback->funcs.decode == NULL)
610 return pb_skip_field(stream, wire_type);
612 if (wire_type == PB_WT_STRING)
614 pb_istream_t substream;
616 if (!pb_make_string_substream(stream, &substream))
621 if (!pCallback->funcs.decode(&substream, iter->pos, arg))
622 PB_RETURN_ERROR(stream, "callback failed");
623 } while (substream.bytes_left);
625 pb_close_string_substream(stream, &substream);
630 /* Copy the single scalar value to stack.
631 * This is required so that we can limit the stream length,
632 * which in turn allows to use same callback for packed and
633 * not-packed fields. */
634 pb_istream_t substream;
635 pb_byte_t buffer[10];
636 size_t size = sizeof(buffer);
638 if (!read_raw_value(stream, wire_type, buffer, &size))
640 substream = pb_istream_from_buffer(buffer, size);
642 return pCallback->funcs.decode(&substream, iter->pos, arg);
646 static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
648 #ifdef PB_ENABLE_MALLOC
649 /* When decoding an oneof field, check if there is old data that must be
651 if (PB_HTYPE(iter->pos->type) == PB_HTYPE_ONEOF)
653 if (!pb_release_union_field(stream, iter))
658 switch (PB_ATYPE(iter->pos->type))
660 case PB_ATYPE_STATIC:
661 return decode_static_field(stream, wire_type, iter);
663 case PB_ATYPE_POINTER:
664 return decode_pointer_field(stream, wire_type, iter);
666 case PB_ATYPE_CALLBACK:
667 return decode_callback_field(stream, wire_type, iter);
670 PB_RETURN_ERROR(stream, "invalid field type");
674 static void iter_from_extension(pb_field_iter_t *iter, pb_extension_t *extension)
676 /* Fake a field iterator for the extension field.
677 * It is not actually safe to advance this iterator, but decode_field
678 * will not even try to. */
679 const pb_field_t *field = (const pb_field_t*)extension->type->arg;
680 (void)pb_field_iter_begin(iter, field, extension->dest);
681 iter->pData = extension->dest;
682 iter->pSize = &extension->found;
684 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
686 /* For pointer extensions, the pointer is stored directly
687 * in the extension structure. This avoids having an extra
689 iter->pData = &extension->dest;
693 /* Default handler for extension fields. Expects a pb_field_t structure
694 * in extension->type->arg. */
695 static bool checkreturn default_extension_decoder(pb_istream_t *stream,
696 pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type)
698 const pb_field_t *field = (const pb_field_t*)extension->type->arg;
699 pb_field_iter_t iter;
701 if (field->tag != tag)
704 iter_from_extension(&iter, extension);
705 extension->found = true;
706 return decode_field(stream, wire_type, &iter);
709 /* Try to decode an unknown field as an extension field. Tries each extension
710 * decoder in turn, until one of them handles the field or loop ends. */
711 static bool checkreturn decode_extension(pb_istream_t *stream,
712 uint32_t tag, pb_wire_type_t wire_type, pb_field_iter_t *iter)
714 pb_extension_t *extension = *(pb_extension_t* const *)iter->pData;
715 size_t pos = stream->bytes_left;
717 while (extension != NULL && pos == stream->bytes_left)
720 if (extension->type->decode)
721 status = extension->type->decode(stream, extension, tag, wire_type);
723 status = default_extension_decoder(stream, extension, tag, wire_type);
728 extension = extension->next;
734 /* Step through the iterator until an extension field is found or until all
735 * entries have been checked. There can be only one extension field per
736 * message. Returns false if no extension field is found. */
737 static bool checkreturn find_extension_field(pb_field_iter_t *iter)
739 const pb_field_t *start = iter->pos;
742 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_EXTENSION)
744 (void)pb_field_iter_next(iter);
745 } while (iter->pos != start);
750 /* Initialize message fields to default values, recursively */
751 static void pb_field_set_to_default(pb_field_iter_t *iter)
754 type = iter->pos->type;
756 if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
758 pb_extension_t *ext = *(pb_extension_t* const *)iter->pData;
761 pb_field_iter_t ext_iter;
763 iter_from_extension(&ext_iter, ext);
764 pb_field_set_to_default(&ext_iter);
768 else if (PB_ATYPE(type) == PB_ATYPE_STATIC)
770 bool init_data = true;
771 if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL)
773 /* Set has_field to false. Still initialize the optional field
775 *(bool*)iter->pSize = false;
777 else if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
778 PB_HTYPE(type) == PB_HTYPE_ONEOF)
780 /* REPEATED: Set array count to 0, no need to initialize contents.
781 ONEOF: Set which_field to 0. */
782 *(pb_size_t*)iter->pSize = 0;
788 if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
790 /* Initialize submessage to defaults */
791 pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, iter->pData);
793 else if (iter->pos->ptr != NULL)
795 /* Initialize to default value */
796 memcpy(iter->pData, iter->pos->ptr, iter->pos->data_size);
800 /* Initialize to zeros */
801 memset(iter->pData, 0, iter->pos->data_size);
805 else if (PB_ATYPE(type) == PB_ATYPE_POINTER)
807 /* Initialize the pointer to NULL. */
808 *(void**)iter->pData = NULL;
810 /* Initialize array count to 0. */
811 if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
812 PB_HTYPE(type) == PB_HTYPE_ONEOF)
814 *(pb_size_t*)iter->pSize = 0;
817 else if (PB_ATYPE(type) == PB_ATYPE_CALLBACK)
819 /* Don't overwrite callback */
823 static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct)
825 pb_field_iter_t iter;
827 if (!pb_field_iter_begin(&iter, fields, dest_struct))
828 return; /* Empty message type */
832 pb_field_set_to_default(&iter);
833 } while (pb_field_iter_next(&iter));
836 /*********************
837 * Decode all fields *
838 *********************/
840 bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
842 uint32_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 31) / 32] = {0, 0};
843 const uint32_t allbits = ~(uint32_t)0;
844 uint32_t extension_range_start = 0;
845 pb_field_iter_t iter;
847 /* Return value ignored, as empty message types will be correctly handled by
848 * pb_field_iter_find() anyway. */
849 (void)pb_field_iter_begin(&iter, fields, dest_struct);
851 while (stream->bytes_left)
854 pb_wire_type_t wire_type;
857 if (!pb_decode_tag(stream, &wire_type, &tag, &eof))
865 if (!pb_field_iter_find(&iter, tag))
867 /* No match found, check if it matches an extension. */
868 if (tag >= extension_range_start)
870 if (!find_extension_field(&iter))
871 extension_range_start = (uint32_t)-1;
873 extension_range_start = iter.pos->tag;
875 if (tag >= extension_range_start)
877 size_t pos = stream->bytes_left;
879 if (!decode_extension(stream, tag, wire_type, &iter))
882 if (pos != stream->bytes_left)
884 /* The field was handled */
890 /* No match found, skip data */
891 if (!pb_skip_field(stream, wire_type))
896 if (PB_HTYPE(iter.pos->type) == PB_HTYPE_REQUIRED
897 && iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
899 uint32_t tmp = ((uint32_t)1 << (iter.required_field_index & 31));
900 fields_seen[iter.required_field_index >> 5] |= tmp;
903 if (!decode_field(stream, wire_type, &iter))
907 /* Check that all required fields were present. */
909 /* First figure out the number of required fields by
910 * seeking to the end of the field array. Usually we
911 * are already close to end after decoding.
913 unsigned req_field_count;
917 req_field_count = iter.required_field_index;
918 last_type = iter.pos->type;
919 } while (pb_field_iter_next(&iter));
921 /* Fixup if last field was also required. */
922 if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED && iter.pos->tag != 0)
925 if (req_field_count > 0)
927 /* Check the whole words */
928 for (i = 0; i < (req_field_count >> 5); i++)
930 if (fields_seen[i] != allbits)
931 PB_RETURN_ERROR(stream, "missing required field");
934 /* Check the remaining bits */
935 if (fields_seen[req_field_count >> 5] != (allbits >> (32 - (req_field_count & 31))))
936 PB_RETURN_ERROR(stream, "missing required field");
943 bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
946 pb_message_set_to_defaults(fields, dest_struct);
947 status = pb_decode_noinit(stream, fields, dest_struct);
949 #ifdef PB_ENABLE_MALLOC
951 pb_release(fields, dest_struct);
957 bool pb_decode_delimited(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
959 pb_istream_t substream;
962 if (!pb_make_string_substream(stream, &substream))
965 status = pb_decode(&substream, fields, dest_struct);
966 pb_close_string_substream(stream, &substream);
970 #ifdef PB_ENABLE_MALLOC
971 /* Given an oneof field, if there has already been a field inside this oneof,
972 * release it before overwriting with a different one. */
973 static bool pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *iter)
975 pb_size_t old_tag = *(pb_size_t*)iter->pSize; /* Previous which_ value */
976 pb_size_t new_tag = iter->pos->tag; /* New which_ value */
979 return true; /* Ok, no old data in union */
981 if (old_tag == new_tag)
982 return true; /* Ok, old data is of same type => merge */
984 /* Release old data. The find can fail if the message struct contains
986 if (!pb_field_iter_find(iter, old_tag))
987 PB_RETURN_ERROR(stream, "invalid union tag");
989 pb_release_single_field(iter);
991 /* Restore iterator to where it should be.
992 * This shouldn't fail unless the pb_field_t structure is corrupted. */
993 if (!pb_field_iter_find(iter, new_tag))
994 PB_RETURN_ERROR(stream, "iterator error");
999 static void pb_release_single_field(const pb_field_iter_t *iter)
1002 type = iter->pos->type;
1004 if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
1006 if (*(pb_size_t*)iter->pSize != iter->pos->tag)
1007 return; /* This is not the current field in the union */
1010 /* Release anything contained inside an extension or submsg.
1011 * This has to be done even if the submsg itself is statically
1013 if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
1015 /* Release fields from all extensions in the linked list */
1016 pb_extension_t *ext = *(pb_extension_t**)iter->pData;
1019 pb_field_iter_t ext_iter;
1020 iter_from_extension(&ext_iter, ext);
1021 pb_release_single_field(&ext_iter);
1025 else if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)
1027 /* Release fields in submessage or submsg array */
1028 void *pItem = iter->pData;
1029 pb_size_t count = 1;
1031 if (PB_ATYPE(type) == PB_ATYPE_POINTER)
1033 pItem = *(void**)iter->pData;
1036 if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
1038 count = *(pb_size_t*)iter->pSize;
1040 if (PB_ATYPE(type) == PB_ATYPE_STATIC && count > iter->pos->array_size)
1042 /* Protect against corrupted _count fields */
1043 count = iter->pos->array_size;
1051 pb_release((const pb_field_t*)iter->pos->ptr, pItem);
1052 pItem = (char*)pItem + iter->pos->data_size;
1057 if (PB_ATYPE(type) == PB_ATYPE_POINTER)
1059 if (PB_HTYPE(type) == PB_HTYPE_REPEATED &&
1060 (PB_LTYPE(type) == PB_LTYPE_STRING ||
1061 PB_LTYPE(type) == PB_LTYPE_BYTES))
1063 /* Release entries in repeated string or bytes array */
1064 void **pItem = *(void***)iter->pData;
1065 pb_size_t count = *(pb_size_t*)iter->pSize;
1073 if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
1075 /* We are going to release the array, so set the size to 0 */
1076 *(pb_size_t*)iter->pSize = 0;
1079 /* Release main item */
1080 pb_free(*(void**)iter->pData);
1081 *(void**)iter->pData = NULL;
1085 void pb_release(const pb_field_t fields[], void *dest_struct)
1087 pb_field_iter_t iter;
1090 return; /* Ignore NULL pointers, similar to free() */
1092 if (!pb_field_iter_begin(&iter, fields, dest_struct))
1093 return; /* Empty message type */
1097 pb_release_single_field(&iter);
1098 } while (pb_field_iter_next(&iter));
1102 /* Field decoders */
1104 bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
1107 if (!pb_decode_varint(stream, &value))
1111 *dest = (int64_t)(~(value >> 1));
1113 *dest = (int64_t)(value >> 1);
1118 bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
1122 if (!pb_read(stream, bytes, 4))
1125 *(uint32_t*)dest = ((uint32_t)bytes[0] << 0) |
1126 ((uint32_t)bytes[1] << 8) |
1127 ((uint32_t)bytes[2] << 16) |
1128 ((uint32_t)bytes[3] << 24);
1132 bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
1136 if (!pb_read(stream, bytes, 8))
1139 *(uint64_t*)dest = ((uint64_t)bytes[0] << 0) |
1140 ((uint64_t)bytes[1] << 8) |
1141 ((uint64_t)bytes[2] << 16) |
1142 ((uint64_t)bytes[3] << 24) |
1143 ((uint64_t)bytes[4] << 32) |
1144 ((uint64_t)bytes[5] << 40) |
1145 ((uint64_t)bytes[6] << 48) |
1146 ((uint64_t)bytes[7] << 56);
1151 static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1156 if (!pb_decode_varint(stream, &value))
1159 /* See issue 97: Google's C++ protobuf allows negative varint values to
1160 * be cast as int32_t, instead of the int64_t that should be used when
1161 * encoding. Previous nanopb versions had a bug in encoding. In order to
1162 * not break decoding of such messages, we cast <=32 bit fields to
1163 * int32_t first to get the sign correct.
1165 if (field->data_size == sizeof(int64_t))
1166 svalue = (int64_t)value;
1168 svalue = (int32_t)value;
1170 /* Cast to the proper field size, while checking for overflows */
1171 if (field->data_size == sizeof(int64_t))
1172 clamped = *(int64_t*)dest = svalue;
1173 else if (field->data_size == sizeof(int32_t))
1174 clamped = *(int32_t*)dest = (int32_t)svalue;
1175 else if (field->data_size == sizeof(int_least16_t))
1176 clamped = *(int_least16_t*)dest = (int_least16_t)svalue;
1177 else if (field->data_size == sizeof(int_least8_t))
1178 clamped = *(int_least8_t*)dest = (int_least8_t)svalue;
1180 PB_RETURN_ERROR(stream, "invalid data_size");
1182 if (clamped != svalue)
1183 PB_RETURN_ERROR(stream, "integer too large");
1188 static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1190 uint64_t value, clamped;
1191 if (!pb_decode_varint(stream, &value))
1194 /* Cast to the proper field size, while checking for overflows */
1195 if (field->data_size == sizeof(uint64_t))
1196 clamped = *(uint64_t*)dest = value;
1197 else if (field->data_size == sizeof(uint32_t))
1198 clamped = *(uint32_t*)dest = (uint32_t)value;
1199 else if (field->data_size == sizeof(uint_least16_t))
1200 clamped = *(uint_least16_t*)dest = (uint_least16_t)value;
1201 else if (field->data_size == sizeof(uint_least8_t))
1202 clamped = *(uint_least8_t*)dest = (uint_least8_t)value;
1204 PB_RETURN_ERROR(stream, "invalid data_size");
1206 if (clamped != value)
1207 PB_RETURN_ERROR(stream, "integer too large");
1212 static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
1214 int64_t value, clamped;
1215 if (!pb_decode_svarint(stream, &value))
1218 /* Cast to the proper field size, while checking for overflows */
1219 if (field->data_size == sizeof(int64_t))
1220 clamped = *(int64_t*)dest = value;
1221 else if (field->data_size == sizeof(int32_t))
1222 clamped = *(int32_t*)dest = (int32_t)value;
1223 else if (field->data_size == sizeof(int_least16_t))
1224 clamped = *(int_least16_t*)dest = (int_least16_t)value;
1225 else if (field->data_size == sizeof(int_least8_t))
1226 clamped = *(int_least8_t*)dest = (int_least8_t)value;
1228 PB_RETURN_ERROR(stream, "invalid data_size");
1230 if (clamped != value)
1231 PB_RETURN_ERROR(stream, "integer too large");
1236 static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest)
1239 return pb_decode_fixed32(stream, dest);
1242 static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest)
1245 return pb_decode_fixed64(stream, dest);
1248 static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest)
1252 pb_bytes_array_t *bdest;
1254 if (!pb_decode_varint32(stream, &size))
1257 if (size > PB_SIZE_MAX)
1258 PB_RETURN_ERROR(stream, "bytes overflow");
1260 alloc_size = PB_BYTES_ARRAY_T_ALLOCSIZE(size);
1261 if (size > alloc_size)
1262 PB_RETURN_ERROR(stream, "size too large");
1264 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
1266 #ifndef PB_ENABLE_MALLOC
1267 PB_RETURN_ERROR(stream, "no malloc support");
1269 if (!allocate_field(stream, dest, alloc_size, 1))
1271 bdest = *(pb_bytes_array_t**)dest;
1276 if (PB_LTYPE(field->type) == PB_LTYPE_FIXED_LENGTH_BYTES) {
1277 if (size != field->data_size)
1278 PB_RETURN_ERROR(stream, "incorrect inline bytes size");
1279 return pb_read(stream, (pb_byte_t*)dest, field->data_size);
1282 if (alloc_size > field->data_size)
1283 PB_RETURN_ERROR(stream, "bytes overflow");
1284 bdest = (pb_bytes_array_t*)dest;
1287 bdest->size = (pb_size_t)size;
1288 return pb_read(stream, bdest->bytes, size);
1291 static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest)
1296 if (!pb_decode_varint32(stream, &size))
1299 /* Space for null terminator */
1300 alloc_size = size + 1;
1302 if (alloc_size < size)
1303 PB_RETURN_ERROR(stream, "size too large");
1305 if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
1307 #ifndef PB_ENABLE_MALLOC
1308 PB_RETURN_ERROR(stream, "no malloc support");
1310 if (!allocate_field(stream, dest, alloc_size, 1))
1312 dest = *(void**)dest;
1317 if (alloc_size > field->data_size)
1318 PB_RETURN_ERROR(stream, "string overflow");
1321 status = pb_read(stream, (pb_byte_t*)dest, size);
1322 *((pb_byte_t*)dest + size) = 0;
1326 static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest)
1329 pb_istream_t substream;
1330 const pb_field_t* submsg_fields = (const pb_field_t*)field->ptr;
1332 if (!pb_make_string_substream(stream, &substream))
1335 if (field->ptr == NULL)
1336 PB_RETURN_ERROR(stream, "invalid field descriptor");
1338 /* New array entries need to be initialized, while required and optional
1339 * submessages have already been initialized in the top-level pb_decode. */
1340 if (PB_HTYPE(field->type) == PB_HTYPE_REPEATED)
1341 status = pb_decode(&substream, submsg_fields, dest);
1343 status = pb_decode_noinit(&substream, submsg_fields, dest);
1345 pb_close_string_substream(stream, &substream);