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pigweed / third_party / github / nanopb / nanopb / b7e02785c93a995277205a02c53c45aad8aebd9c / . / pb_decode.c
blob: b1948254d5938910012acbff2db66455f93793aa [file] [log] [blame]
/* pb_decode.c -- decode a protobuf using minimal resources
*
* 2011 Petteri Aimonen <jpa@kapsi.fi>
*/
/* Use the GCC warn_unused_result attribute to check that all return values
* are propagated correctly. On other compilers and gcc before 3.4.0 just
* ignore the annotation.
*/
#if !defined(__GNUC__) || ( __GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
#define checkreturn
#else
#define checkreturn __attribute__((warn_unused_result))
#endif
#include "pb.h"
#include "pb_decode.h"
#include "pb_common.h"
/**************************************
* Declarations internal to this file *
**************************************/
static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count);
static bool checkreturn pb_decode_varint32_eof(pb_istream_t *stream, uint32_t *dest, bool *eof);
static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size);
static bool checkreturn decode_basic_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field);
static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field);
static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field);
static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field);
static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field);
static bool checkreturn default_extension_decoder(pb_istream_t *stream, pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type);
static bool checkreturn decode_extension(pb_istream_t *stream, uint32_t tag, pb_wire_type_t wire_type, pb_extension_t *extension);
static bool pb_field_set_to_default(pb_field_iter_t *field);
static bool pb_message_set_to_defaults(pb_field_iter_t *iter);
static bool checkreturn pb_dec_bool(pb_istream_t *stream, const pb_field_iter_t *field);
static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_iter_t *field);
static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_iter_t *field);
static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_iter_t *field);
static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_iter_t *field);
static bool checkreturn pb_dec_fixed_length_bytes(pb_istream_t *stream, const pb_field_iter_t *field);
static bool checkreturn pb_skip_varint(pb_istream_t *stream);
static bool checkreturn pb_skip_string(pb_istream_t *stream);
#ifdef PB_ENABLE_MALLOC
static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size);
static void initialize_pointer_field(void *pItem, pb_field_iter_t *field);
static bool checkreturn pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *field);
static void pb_release_single_field(pb_field_iter_t *field);
#endif
#ifdef PB_WITHOUT_64BIT
#define pb_int64_t int32_t
#define pb_uint64_t uint32_t
#else
#define pb_int64_t int64_t
#define pb_uint64_t uint64_t
#endif
#define PB_WT_PACKED ((pb_wire_type_t)0xFF)
typedef struct {
uint32_t bitfield[(PB_MAX_REQUIRED_FIELDS + 31) / 32];
} pb_fields_seen_t;
/*******************************
* pb_istream_t implementation *
*******************************/
static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
{
size_t i;
const pb_byte_t *source = (const pb_byte_t*)stream->state;
stream->state = (pb_byte_t*)stream->state + count;
if (buf != NULL)
{
for (i = 0; i < count; i++)
buf[i] = source[i];
}
return true;
}
bool checkreturn pb_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
{
if (count == 0)
return true;
#ifndef PB_BUFFER_ONLY
if (buf == NULL && stream->callback != buf_read)
{
/* Skip input bytes */
pb_byte_t tmp[16];
while (count > 16)
{
if (!pb_read(stream, tmp, 16))
return false;
count -= 16;
}
return pb_read(stream, tmp, count);
}
#endif
if (stream->bytes_left < count)
PB_RETURN_ERROR(stream, "end-of-stream");
#ifndef PB_BUFFER_ONLY
if (!stream->callback(stream, buf, count))
PB_RETURN_ERROR(stream, "io error");
#else
if (!buf_read(stream, buf, count))
return false;
#endif
stream->bytes_left -= count;
return true;
}
/* Read a single byte from input stream. buf may not be NULL.
* This is an optimization for the varint decoding. */
static bool checkreturn pb_readbyte(pb_istream_t *stream, pb_byte_t *buf)
{
if (stream->bytes_left == 0)
PB_RETURN_ERROR(stream, "end-of-stream");
#ifndef PB_BUFFER_ONLY
if (!stream->callback(stream, buf, 1))
PB_RETURN_ERROR(stream, "io error");
#else
*buf = *(const pb_byte_t*)stream->state;
stream->state = (pb_byte_t*)stream->state + 1;
#endif
stream->bytes_left--;
return true;
}
pb_istream_t pb_istream_from_buffer(const pb_byte_t *buf, size_t msglen)
{
pb_istream_t stream;
/* Cast away the const from buf without a compiler error. We are
* careful to use it only in a const manner in the callbacks.
*/
union {
void *state;
const void *c_state;
} state;
#ifdef PB_BUFFER_ONLY
stream.callback = NULL;
#else
stream.callback = &buf_read;
#endif
state.c_state = buf;
stream.state = state.state;
stream.bytes_left = msglen;
#ifndef PB_NO_ERRMSG
stream.errmsg = NULL;
#endif
return stream;
}
/********************
* Helper functions *
********************/
static bool checkreturn pb_decode_varint32_eof(pb_istream_t *stream, uint32_t *dest, bool *eof)
{
pb_byte_t byte;
uint32_t result;
if (!pb_readbyte(stream, &byte))
{
if (stream->bytes_left == 0)
{
if (eof)
{
*eof = true;
}
}
return false;
}
if ((byte & 0x80) == 0)
{
/* Quick case, 1 byte value */
result = byte;
}
else
{
/* Multibyte case */
uint_fast8_t bitpos = 7;
result = byte & 0x7F;
do
{
if (!pb_readbyte(stream, &byte))
return false;
if (bitpos >= 32)
{
/* Note: The varint could have trailing 0x80 bytes, or 0xFF for negative. */
pb_byte_t sign_extension = (bitpos < 63) ? 0xFF : 0x01;
bool valid_extension = ((byte & 0x7F) == 0x00 ||
((result >> 31) != 0 && byte == sign_extension));
if (bitpos >= 64 || !valid_extension)
{
PB_RETURN_ERROR(stream, "varint overflow");
}
}
else
{
result |= (uint32_t)(byte & 0x7F) << bitpos;
}
bitpos = (uint_fast8_t)(bitpos + 7);
} while (byte & 0x80);
if (bitpos == 35 && (byte & 0x70) != 0)
{
/* The last byte was at bitpos=28, so only bottom 4 bits fit. */
PB_RETURN_ERROR(stream, "varint overflow");
}
}
*dest = result;
return true;
}
bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
{
return pb_decode_varint32_eof(stream, dest, NULL);
}
#ifndef PB_WITHOUT_64BIT
bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
{
pb_byte_t byte;
uint_fast8_t bitpos = 0;
uint64_t result = 0;
do
{
if (bitpos >= 64)
PB_RETURN_ERROR(stream, "varint overflow");
if (!pb_readbyte(stream, &byte))
return false;
result |= (uint64_t)(byte & 0x7F) << bitpos;
bitpos = (uint_fast8_t)(bitpos + 7);
} while (byte & 0x80);
*dest = result;
return true;
}
#endif
bool checkreturn pb_skip_varint(pb_istream_t *stream)
{
pb_byte_t byte;
do
{
if (!pb_read(stream, &byte, 1))
return false;
} while (byte & 0x80);
return true;
}
bool checkreturn pb_skip_string(pb_istream_t *stream)
{
uint32_t length;
if (!pb_decode_varint32(stream, &length))
return false;
if ((size_t)length != length)
{
PB_RETURN_ERROR(stream, "size too large");
}
return pb_read(stream, NULL, (size_t)length);
}
bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof)
{
uint32_t temp;
*eof = false;
*wire_type = (pb_wire_type_t) 0;
*tag = 0;
if (!pb_decode_varint32_eof(stream, &temp, eof))
{
return false;
}
*tag = temp >> 3;
*wire_type = (pb_wire_type_t)(temp & 7);
return true;
}
bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
{
switch (wire_type)
{
case PB_WT_VARINT: return pb_skip_varint(stream);
case PB_WT_64BIT: return pb_read(stream, NULL, 8);
case PB_WT_STRING: return pb_skip_string(stream);
case PB_WT_32BIT: return pb_read(stream, NULL, 4);
default: PB_RETURN_ERROR(stream, "invalid wire_type");
}
}
/* Read a raw value to buffer, for the purpose of passing it to callback as
* a substream. Size is maximum size on call, and actual size on return.
*/
static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size)
{
size_t max_size = *size;
switch (wire_type)
{
case PB_WT_VARINT:
*size = 0;
do
{
(*size)++;
if (*size > max_size)
PB_RETURN_ERROR(stream, "varint overflow");
if (!pb_read(stream, buf, 1))
return false;
} while (*buf++ & 0x80);
return true;
case PB_WT_64BIT:
*size = 8;
return pb_read(stream, buf, 8);
case PB_WT_32BIT:
*size = 4;
return pb_read(stream, buf, 4);
case PB_WT_STRING:
/* Calling read_raw_value with a PB_WT_STRING is an error.
* Explicitly handle this case and fallthrough to default to avoid
* compiler warnings.
*/
default: PB_RETURN_ERROR(stream, "invalid wire_type");
}
}
/* Decode string length from stream and return a substream with limited length.
* Remember to close the substream using pb_close_string_substream().
*/
bool checkreturn pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
{
uint32_t size;
if (!pb_decode_varint32(stream, &size))
return false;
*substream = *stream;
if (substream->bytes_left < size)
PB_RETURN_ERROR(stream, "parent stream too short");
substream->bytes_left = (size_t)size;
stream->bytes_left -= (size_t)size;
return true;
}
bool checkreturn pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream)
{
if (substream->bytes_left) {
if (!pb_read(substream, NULL, substream->bytes_left))
return false;
}
stream->state = substream->state;
#ifndef PB_NO_ERRMSG
stream->errmsg = substream->errmsg;
#endif
return true;
}
/*************************
* Decode a single field *
*************************/
static bool checkreturn decode_basic_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field)
{
switch (PB_LTYPE(field->type))
{
case PB_LTYPE_BOOL:
if (wire_type != PB_WT_VARINT && wire_type != PB_WT_PACKED)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_dec_bool(stream, field);
case PB_LTYPE_VARINT:
case PB_LTYPE_UVARINT:
case PB_LTYPE_SVARINT:
if (wire_type != PB_WT_VARINT && wire_type != PB_WT_PACKED)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_dec_varint(stream, field);
case PB_LTYPE_FIXED32:
if (wire_type != PB_WT_32BIT && wire_type != PB_WT_PACKED)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_decode_fixed32(stream, field->pData);
case PB_LTYPE_FIXED64:
if (wire_type != PB_WT_64BIT && wire_type != PB_WT_PACKED)
PB_RETURN_ERROR(stream, "wrong wire type");
#ifdef PB_CONVERT_DOUBLE_FLOAT
if (field->data_size == sizeof(float))
{
return pb_decode_double_as_float(stream, (float*)field->pData);
}
#endif
#ifdef PB_WITHOUT_64BIT
PB_RETURN_ERROR(stream, "invalid data_size");
#else
return pb_decode_fixed64(stream, field->pData);
#endif
case PB_LTYPE_BYTES:
if (wire_type != PB_WT_STRING)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_dec_bytes(stream, field);
case PB_LTYPE_STRING:
if (wire_type != PB_WT_STRING)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_dec_string(stream, field);
case PB_LTYPE_SUBMESSAGE:
case PB_LTYPE_SUBMSG_W_CB:
if (wire_type != PB_WT_STRING)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_dec_submessage(stream, field);
case PB_LTYPE_FIXED_LENGTH_BYTES:
if (wire_type != PB_WT_STRING)
PB_RETURN_ERROR(stream, "wrong wire type");
return pb_dec_fixed_length_bytes(stream, field);
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
}
static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field)
{
switch (PB_HTYPE(field->type))
{
case PB_HTYPE_REQUIRED:
return decode_basic_field(stream, wire_type, field);
case PB_HTYPE_OPTIONAL:
if (field->pSize != NULL)
*(bool*)field->pSize = true;
return decode_basic_field(stream, wire_type, field);
case PB_HTYPE_REPEATED:
if (wire_type == PB_WT_STRING
&& PB_LTYPE(field->type) <= PB_LTYPE_LAST_PACKABLE)
{
/* Packed array */
bool status = true;
pb_istream_t substream;
pb_size_t *size = (pb_size_t*)field->pSize;
field->pData = (char*)field->pField + field->data_size * (*size);
if (!pb_make_string_substream(stream, &substream))
return false;
while (substream.bytes_left > 0 && *size < field->array_size)
{
if (!decode_basic_field(&substream, PB_WT_PACKED, field))
{
status = false;
break;
}
(*size)++;
field->pData = (char*)field->pData + field->data_size;
}
if (substream.bytes_left != 0)
PB_RETURN_ERROR(stream, "array overflow");
if (!pb_close_string_substream(stream, &substream))
return false;
return status;
}
else
{
/* Repeated field */
pb_size_t *size = (pb_size_t*)field->pSize;
field->pData = (char*)field->pField + field->data_size * (*size);
if ((*size)++ >= field->array_size)
PB_RETURN_ERROR(stream, "array overflow");
return decode_basic_field(stream, wire_type, field);
}
case PB_HTYPE_ONEOF:
if (PB_LTYPE_IS_SUBMSG(field->type) &&
*(pb_size_t*)field->pSize != field->tag)
{
/* We memset to zero so that any callbacks are set to NULL.
* This is because the callbacks might otherwise have values
* from some other union field.
* If callbacks are needed inside oneof field, use .proto
* option submsg_callback to have a separate callback function
* that can set the fields before submessage is decoded.
* pb_dec_submessage() will set any default values. */
memset(field->pData, 0, (size_t)field->data_size);
/* Set default values for the submessage fields. */
if (field->submsg_desc->default_value != NULL ||
field->submsg_desc->field_callback != NULL ||
field->submsg_desc->submsg_info[0] != NULL)
{
pb_field_iter_t submsg_iter;
if (pb_field_iter_begin(&submsg_iter, field->submsg_desc, field->pData))
{
if (!pb_message_set_to_defaults(&submsg_iter))
PB_RETURN_ERROR(stream, "failed to set defaults");
}
}
}
*(pb_size_t*)field->pSize = field->tag;
return decode_basic_field(stream, wire_type, field);
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
}
#ifdef PB_ENABLE_MALLOC
/* Allocate storage for the field and store the pointer at iter->pData.
* array_size is the number of entries to reserve in an array.
* Zero size is not allowed, use pb_free() for releasing.
*/
static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size)
{
void *ptr = *(void**)pData;
if (data_size == 0 || array_size == 0)
PB_RETURN_ERROR(stream, "invalid size");
#ifdef __AVR__
/* Workaround for AVR libc bug 53284: http://savannah.nongnu.org/bugs/?53284
* Realloc to size of 1 byte can cause corruption of the malloc structures.
*/
if (data_size == 1 && array_size == 1)
{
data_size = 2;
}
#endif
/* Check for multiplication overflows.
* This code avoids the costly division if the sizes are small enough.
* Multiplication is safe as long as only half of bits are set
* in either multiplicand.
*/
{
const size_t check_limit = (size_t)1 << (sizeof(size_t) * 4);
if (data_size >= check_limit || array_size >= check_limit)
{
const size_t size_max = (size_t)-1;
if (size_max / array_size < data_size)
{
PB_RETURN_ERROR(stream, "size too large");
}
}
}
/* Allocate new or expand previous allocation */
/* Note: on failure the old pointer will remain in the structure,
* the message must be freed by caller also on error return. */
ptr = pb_realloc(ptr, array_size * data_size);
if (ptr == NULL)
PB_RETURN_ERROR(stream, "realloc failed");
*(void**)pData = ptr;
return true;
}
/* Clear a newly allocated item in case it contains a pointer, or is a submessage. */
static void initialize_pointer_field(void *pItem, pb_field_iter_t *field)
{
if (PB_LTYPE(field->type) == PB_LTYPE_STRING ||
PB_LTYPE(field->type) == PB_LTYPE_BYTES)
{
*(void**)pItem = NULL;
}
else if (PB_LTYPE_IS_SUBMSG(field->type))
{
/* We memset to zero so that any callbacks are set to NULL.
* Default values will be set by pb_dec_submessage(). */
memset(pItem, 0, field->data_size);
}
}
#endif
static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field)
{
#ifndef PB_ENABLE_MALLOC
PB_UNUSED(wire_type);
PB_UNUSED(field);
PB_RETURN_ERROR(stream, "no malloc support");
#else
switch (PB_HTYPE(field->type))
{
case PB_HTYPE_REQUIRED:
case PB_HTYPE_OPTIONAL:
case PB_HTYPE_ONEOF:
if (PB_LTYPE_IS_SUBMSG(field->type) && *(void**)field->pField != NULL)
{
/* Duplicate field, have to release the old allocation first. */
/* FIXME: Does this work correctly for oneofs? */
pb_release_single_field(field);
}
if (PB_HTYPE(field->type) == PB_HTYPE_ONEOF)
{
*(pb_size_t*)field->pSize = field->tag;
}
if (PB_LTYPE(field->type) == PB_LTYPE_STRING ||
PB_LTYPE(field->type) == PB_LTYPE_BYTES)
{
/* pb_dec_string and pb_dec_bytes handle allocation themselves */
field->pData = field->pField;
return decode_basic_field(stream, wire_type, field);
}
else
{
if (!allocate_field(stream, field->pField, field->data_size, 1))
return false;
field->pData = *(void**)field->pField;
initialize_pointer_field(field->pData, field);
return decode_basic_field(stream, wire_type, field);
}
case PB_HTYPE_REPEATED:
if (wire_type == PB_WT_STRING
&& PB_LTYPE(field->type) <= PB_LTYPE_LAST_PACKABLE)
{
/* Packed array, multiple items come in at once. */
bool status = true;
pb_size_t *size = (pb_size_t*)field->pSize;
size_t allocated_size = *size;
pb_istream_t substream;
if (!pb_make_string_substream(stream, &substream))
return false;
while (substream.bytes_left)
{
if (*size == PB_SIZE_MAX)
{
#ifndef PB_NO_ERRMSG
stream->errmsg = "too many array entries";
#endif
status = false;
break;
}
if ((size_t)*size + 1 > allocated_size)
{
/* Allocate more storage. This tries to guess the
* number of remaining entries. Round the division
* upwards. */
size_t remain = (substream.bytes_left - 1) / field->data_size + 1;
if (remain < PB_SIZE_MAX - allocated_size)
allocated_size += remain;
else
allocated_size += 1;
if (!allocate_field(&substream, field->pField, field->data_size, allocated_size))
{
status = false;
break;
}
}
/* Decode the array entry */
field->pData = *(char**)field->pField + field->data_size * (*size);
initialize_pointer_field(field->pData, field);
if (!decode_basic_field(&substream, PB_WT_PACKED, field))
{
status = false;
break;
}
(*size)++;
}
if (!pb_close_string_substream(stream, &substream))
return false;
return status;
}
else
{
/* Normal repeated field, i.e. only one item at a time. */
pb_size_t *size = (pb_size_t*)field->pSize;
if (*size == PB_SIZE_MAX)
PB_RETURN_ERROR(stream, "too many array entries");
if (!allocate_field(stream, field->pField, field->data_size, (size_t)(*size + 1)))
return false;
field->pData = *(char**)field->pField + field->data_size * (*size);
(*size)++;
initialize_pointer_field(field->pData, field);
return decode_basic_field(stream, wire_type, field);
}
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
#endif
}
static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field)
{
if (!field->descriptor->field_callback)
return pb_skip_field(stream, wire_type);
if (wire_type == PB_WT_STRING)
{
pb_istream_t substream;
size_t prev_bytes_left;
if (!pb_make_string_substream(stream, &substream))
return false;
do
{
prev_bytes_left = substream.bytes_left;
if (!field->descriptor->field_callback(&substream, NULL, field))
PB_RETURN_ERROR(stream, "callback failed");
} while (substream.bytes_left > 0 && substream.bytes_left < prev_bytes_left);
if (!pb_close_string_substream(stream, &substream))
return false;
return true;
}
else
{
/* Copy the single scalar value to stack.
* This is required so that we can limit the stream length,
* which in turn allows to use same callback for packed and
* not-packed fields. */
pb_istream_t substream;
pb_byte_t buffer[10];
size_t size = sizeof(buffer);
if (!read_raw_value(stream, wire_type, buffer, &size))
return false;
substream = pb_istream_from_buffer(buffer, size);
return field->descriptor->field_callback(&substream, NULL, field);
}
}
static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *field)
{
#ifdef PB_ENABLE_MALLOC
/* When decoding an oneof field, check if there is old data that must be
* released first. */
if (PB_HTYPE(field->type) == PB_HTYPE_ONEOF)
{
if (!pb_release_union_field(stream, field))
return false;
}
#endif
switch (PB_ATYPE(field->type))
{
case PB_ATYPE_STATIC:
return decode_static_field(stream, wire_type, field);
case PB_ATYPE_POINTER:
return decode_pointer_field(stream, wire_type, field);
case PB_ATYPE_CALLBACK:
return decode_callback_field(stream, wire_type, field);
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
}
/* Default handler for extension fields. Expects to have a pb_msgdesc_t
* pointer in the extension->type->arg field, pointing to a message with
* only one field in it. */
static bool checkreturn default_extension_decoder(pb_istream_t *stream,
pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type)
{
pb_field_iter_t iter;
if (!pb_field_iter_begin_extension(&iter, extension))
PB_RETURN_ERROR(stream, "invalid extension");
if (iter.tag != tag || !iter.message)
return true;
extension->found = true;
return decode_field(stream, wire_type, &iter);
}
/* Try to decode an unknown field as an extension field. Tries each extension
* decoder in turn, until one of them handles the field or loop ends. */
static bool checkreturn decode_extension(pb_istream_t *stream,
uint32_t tag, pb_wire_type_t wire_type, pb_extension_t *extension)
{
size_t pos = stream->bytes_left;
while (extension != NULL && pos == stream->bytes_left)
{
bool status;
if (extension->type->decode)
status = extension->type->decode(stream, extension, tag, wire_type);
else
status = default_extension_decoder(stream, extension, tag, wire_type);
if (!status)
return false;
extension = extension->next;
}
return true;
}
/* Initialize message fields to default values, recursively */
static bool pb_field_set_to_default(pb_field_iter_t *field)
{
pb_type_t type;
type = field->type;
if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
{
pb_extension_t *ext = *(pb_extension_t* const *)field->pData;
while (ext != NULL)
{
pb_field_iter_t ext_iter;
if (pb_field_iter_begin_extension(&ext_iter, ext))
{
ext->found = false;
if (!pb_message_set_to_defaults(&ext_iter))
return false;
}
ext = ext->next;
}
}
else if (PB_ATYPE(type) == PB_ATYPE_STATIC)
{
bool init_data = true;
if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL && field->pSize != NULL)
{
/* Set has_field to false. Still initialize the optional field
* itself also. */
*(bool*)field->pSize = false;
}
else if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
PB_HTYPE(type) == PB_HTYPE_ONEOF)
{
/* REPEATED: Set array count to 0, no need to initialize contents.
ONEOF: Set which_field to 0. */
*(pb_size_t*)field->pSize = 0;
init_data = false;
}
if (init_data)
{
if (PB_LTYPE_IS_SUBMSG(field->type) &&
(field->submsg_desc->default_value != NULL ||
field->submsg_desc->field_callback != NULL ||
field->submsg_desc->submsg_info[0] != NULL))
{
/* Initialize submessage to defaults.
* Only needed if it has default values
* or callback/submessage fields. */
pb_field_iter_t submsg_iter;
if (pb_field_iter_begin(&submsg_iter, field->submsg_desc, field->pData))
{
if (!pb_message_set_to_defaults(&submsg_iter))
return false;
}
}
else
{
/* Initialize to zeros */
memset(field->pData, 0, (size_t)field->data_size);
}
}
}
else if (PB_ATYPE(type) == PB_ATYPE_POINTER)
{
/* Initialize the pointer to NULL. */
*(void**)field->pField = NULL;
/* Initialize array count to 0. */
if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
PB_HTYPE(type) == PB_HTYPE_ONEOF)
{
*(pb_size_t*)field->pSize = 0;
}
}
else if (PB_ATYPE(type) == PB_ATYPE_CALLBACK)
{
/* Don't overwrite callback */
}
return true;
}
static bool pb_message_set_to_defaults(pb_field_iter_t *iter)
{
pb_istream_t defstream = PB_ISTREAM_EMPTY;
uint32_t tag = 0;
pb_wire_type_t wire_type = PB_WT_VARINT;
bool eof;
if (iter->descriptor->default_value)
{
defstream = pb_istream_from_buffer(iter->descriptor->default_value, (size_t)-1);
if (!pb_decode_tag(&defstream, &wire_type, &tag, &eof))
return false;
}
do
{
if (!pb_field_set_to_default(iter))
return false;
if (tag != 0 && iter->tag == tag)
{
/* We have a default value for this field in the defstream */
if (!decode_field(&defstream, wire_type, iter))
return false;
if (!pb_decode_tag(&defstream, &wire_type, &tag, &eof))
return false;
if (iter->pSize)
*(bool*)iter->pSize = false;
}
} while (pb_field_iter_next(iter));
return true;
}
/*********************
* Decode all fields *
*********************/
static bool checkreturn pb_decode_inner(pb_istream_t *stream, const pb_msgdesc_t *fields, void *dest_struct, unsigned int flags)
{
uint32_t extension_range_start = 0;
pb_extension_t *extensions = NULL;
/* 'fixed_count_field' and 'fixed_count_size' track position of a repeated fixed
* count field. This can only handle _one_ repeated fixed count field that
* is unpacked and unordered among other (non repeated fixed count) fields.
*/
pb_size_t fixed_count_field = PB_SIZE_MAX;
pb_size_t fixed_count_size = 0;
pb_size_t fixed_count_total_size = 0;
pb_fields_seen_t fields_seen = {{0, 0}};
const uint32_t allbits = ~(uint32_t)0;
pb_field_iter_t iter;
if (pb_field_iter_begin(&iter, fields, dest_struct))
{
if ((flags & PB_DECODE_NOINIT) == 0)
{
if (!pb_message_set_to_defaults(&iter))
PB_RETURN_ERROR(stream, "failed to set defaults");
}
}
while (stream->bytes_left)
{
uint32_t tag;
pb_wire_type_t wire_type;
bool eof;
if (!pb_decode_tag(stream, &wire_type, &tag, &eof))
{
if (eof)
break;
else
return false;
}
if (tag == 0)
{
if (flags & PB_DECODE_NULLTERMINATED)
{
break;
}
else
{
PB_RETURN_ERROR(stream, "zero tag");
}
}
if (!pb_field_iter_find(&iter, tag) || PB_LTYPE(iter.type) == PB_LTYPE_EXTENSION)
{
/* No match found, check if it matches an extension. */
if (extension_range_start == 0)
{
if (pb_field_iter_find_extension(&iter))
{
extensions = *(pb_extension_t* const *)iter.pData;
extension_range_start = iter.tag;
}
if (!extensions)
{
extension_range_start = (uint32_t)-1;
}
}
if (tag >= extension_range_start)
{
size_t pos = stream->bytes_left;
if (!decode_extension(stream, tag, wire_type, extensions))
return false;
if (pos != stream->bytes_left)
{
/* The field was handled */
continue;
}
}
/* No match found, skip data */
if (!pb_skip_field(stream, wire_type))
return false;
continue;
}
/* If a repeated fixed count field was found, get size from
* 'fixed_count_field' as there is no counter contained in the struct.
*/
if (PB_HTYPE(iter.type) == PB_HTYPE_REPEATED && iter.pSize == &iter.array_size)
{
if (fixed_count_field != iter.index) {
/* If the new fixed count field does not match the previous one,
* check that the previous one is NULL or that it finished
* receiving all the expected data.
*/
if (fixed_count_field != PB_SIZE_MAX &&
fixed_count_size != fixed_count_total_size)
{
PB_RETURN_ERROR(stream, "wrong size for fixed count field");
}
fixed_count_field = iter.index;
fixed_count_size = 0;
fixed_count_total_size = iter.array_size;
}
iter.pSize = &fixed_count_size;
}
if (PB_HTYPE(iter.type) == PB_HTYPE_REQUIRED
&& iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
{
uint32_t tmp = ((uint32_t)1 << (iter.required_field_index & 31));
fields_seen.bitfield[iter.required_field_index >> 5] |= tmp;
}
if (!decode_field(stream, wire_type, &iter))
return false;
}
/* Check that all elements of the last decoded fixed count field were present. */
if (fixed_count_field != PB_SIZE_MAX &&
fixed_count_size != fixed_count_total_size)
{
PB_RETURN_ERROR(stream, "wrong size for fixed count field");
}
/* Check that all required fields were present. */
{
pb_size_t req_field_count = iter.descriptor->required_field_count;
if (req_field_count > 0)
{
pb_size_t i;
if (req_field_count > PB_MAX_REQUIRED_FIELDS)
req_field_count = PB_MAX_REQUIRED_FIELDS;
/* Check the whole words */
for (i = 0; i < (req_field_count >> 5); i++)
{
if (fields_seen.bitfield[i] != allbits)
PB_RETURN_ERROR(stream, "missing required field");
}
/* Check the remaining bits (if any) */
if ((req_field_count & 31) != 0)
{
if (fields_seen.bitfield[req_field_count >> 5] !=
(allbits >> (uint_least8_t)(32 - (req_field_count & 31))))
{
PB_RETURN_ERROR(stream, "missing required field");
}
}
}
}
return true;
}
bool checkreturn pb_decode_ex(pb_istream_t *stream, const pb_msgdesc_t *fields, void *dest_struct, unsigned int flags)
{
bool status;
if ((flags & PB_DECODE_DELIMITED) == 0)
{
status = pb_decode_inner(stream, fields, dest_struct, flags);
}
else
{
pb_istream_t substream;
if (!pb_make_string_substream(stream, &substream))
return false;
status = pb_decode_inner(&substream, fields, dest_struct, flags);
if (!pb_close_string_substream(stream, &substream))
return false;
}
#ifdef PB_ENABLE_MALLOC
if (!status)
pb_release(fields, dest_struct);
#endif
return status;
}
bool checkreturn pb_decode(pb_istream_t *stream, const pb_msgdesc_t *fields, void *dest_struct)
{
bool status;
status = pb_decode_inner(stream, fields, dest_struct, 0);
#ifdef PB_ENABLE_MALLOC
if (!status)
pb_release(fields, dest_struct);
#endif
return status;
}
#ifdef PB_ENABLE_MALLOC
/* Given an oneof field, if there has already been a field inside this oneof,
* release it before overwriting with a different one. */
static bool pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *field)
{
pb_field_iter_t old_field = *field;
pb_size_t old_tag = *(pb_size_t*)field->pSize; /* Previous which_ value */
pb_size_t new_tag = field->tag; /* New which_ value */
if (old_tag == 0)
return true; /* Ok, no old data in union */
if (old_tag == new_tag)
return true; /* Ok, old data is of same type => merge */
/* Release old data. The find can fail if the message struct contains
* invalid data. */
if (!pb_field_iter_find(&old_field, old_tag))
PB_RETURN_ERROR(stream, "invalid union tag");
pb_release_single_field(&old_field);
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
{
/* Initialize the pointer to NULL to make sure it is valid
* even in case of error return. */
*(void**)field->pField = NULL;
field->pData = NULL;
}
return true;
}
static void pb_release_single_field(pb_field_iter_t *field)
{
pb_type_t type;
type = field->type;
if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
{
if (*(pb_size_t*)field->pSize != field->tag)
return; /* This is not the current field in the union */
}
/* Release anything contained inside an extension or submsg.
* This has to be done even if the submsg itself is statically
* allocated. */
if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
{
/* Release fields from all extensions in the linked list */
pb_extension_t *ext = *(pb_extension_t**)field->pData;
while (ext != NULL)
{
pb_field_iter_t ext_iter;
if (pb_field_iter_begin_extension(&ext_iter, ext))
{
pb_release_single_field(&ext_iter);
}
ext = ext->next;
}
}
else if (PB_LTYPE_IS_SUBMSG(type) && PB_ATYPE(type) != PB_ATYPE_CALLBACK)
{
/* Release fields in submessage or submsg array */
pb_size_t count = 1;
if (PB_ATYPE(type) == PB_ATYPE_POINTER)
{
field->pData = *(void**)field->pField;
}
else
{
field->pData = field->pField;
}
if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
{
count = *(pb_size_t*)field->pSize;
if (PB_ATYPE(type) == PB_ATYPE_STATIC && count > field->array_size)
{
/* Protect against corrupted _count fields */
count = field->array_size;
}
}
if (field->pData)
{
for (; count > 0; count--)
{
pb_release(field->submsg_desc, field->pData);
field->pData = (char*)field->pData + field->data_size;
}
}
}
if (PB_ATYPE(type) == PB_ATYPE_POINTER)
{
if (PB_HTYPE(type) == PB_HTYPE_REPEATED &&
(PB_LTYPE(type) == PB_LTYPE_STRING ||
PB_LTYPE(type) == PB_LTYPE_BYTES))
{
/* Release entries in repeated string or bytes array */
void **pItem = *(void***)field->pField;
pb_size_t count = *(pb_size_t*)field->pSize;
for (; count > 0; count--)
{
pb_free(*pItem);
*pItem++ = NULL;
}
}
if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
{
/* We are going to release the array, so set the size to 0 */
*(pb_size_t*)field->pSize = 0;
}
/* Release main pointer */
pb_free(*(void**)field->pField);
*(void**)field->pField = NULL;
}
}
void pb_release(const pb_msgdesc_t *fields, void *dest_struct)
{
pb_field_iter_t iter;
if (!dest_struct)
return; /* Ignore NULL pointers, similar to free() */
if (!pb_field_iter_begin(&iter, fields, dest_struct))
return; /* Empty message type */
do
{
pb_release_single_field(&iter);
} while (pb_field_iter_next(&iter));
}
#endif
/* Field decoders */
bool pb_decode_bool(pb_istream_t *stream, bool *dest)
{
uint32_t value;
if (!pb_decode_varint32(stream, &value))
return false;
*(bool*)dest = (value != 0);
return true;
}
bool pb_decode_svarint(pb_istream_t *stream, pb_int64_t *dest)
{
pb_uint64_t value;
if (!pb_decode_varint(stream, &value))
return false;
if (value & 1)
*dest = (pb_int64_t)(~(value >> 1));
else
*dest = (pb_int64_t)(value >> 1);
return true;
}
bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
{
union {
uint32_t fixed32;
pb_byte_t bytes[4];
} u;
if (!pb_read(stream, u.bytes, 4))
return false;
#if defined(__BYTE_ORDER) && __BYTE_ORDER == __LITTLE_ENDIAN && CHAR_BIT == 8
/* fast path - if we know that we're on little endian, assign directly */
*(uint32_t*)dest = u.fixed32;
#else
*(uint32_t*)dest = ((uint32_t)u.bytes[0] << 0) |
((uint32_t)u.bytes[1] << 8) |
((uint32_t)u.bytes[2] << 16) |
((uint32_t)u.bytes[3] << 24);
#endif
return true;
}
#ifndef PB_WITHOUT_64BIT
bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
{
union {
uint64_t fixed64;
pb_byte_t bytes[8];
} u;
if (!pb_read(stream, u.bytes, 8))
return false;
#if defined(__BYTE_ORDER) && __BYTE_ORDER == __LITTLE_ENDIAN && CHAR_BIT == 8
/* fast path - if we know that we're on little endian, assign directly */
*(uint64_t*)dest = u.fixed64;
#else
*(uint64_t*)dest = ((uint64_t)u.bytes[0] << 0) |
((uint64_t)u.bytes[1] << 8) |
((uint64_t)u.bytes[2] << 16) |
((uint64_t)u.bytes[3] << 24) |
((uint64_t)u.bytes[4] << 32) |
((uint64_t)u.bytes[5] << 40) |
((uint64_t)u.bytes[6] << 48) |
((uint64_t)u.bytes[7] << 56);
#endif
return true;
}
#endif
static bool checkreturn pb_dec_bool(pb_istream_t *stream, const pb_field_iter_t *field)
{
return pb_decode_bool(stream, (bool*)field->pData);
}
static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_iter_t *field)
{
if (PB_LTYPE(field->type) == PB_LTYPE_UVARINT)
{
pb_uint64_t value, clamped;
if (!pb_decode_varint(stream, &value))
return false;
/* Cast to the proper field size, while checking for overflows */
if (field->data_size == sizeof(pb_uint64_t))
clamped = *(pb_uint64_t*)field->pData = value;
else if (field->data_size == sizeof(uint32_t))
clamped = *(uint32_t*)field->pData = (uint32_t)value;
else if (field->data_size == sizeof(uint_least16_t))
clamped = *(uint_least16_t*)field->pData = (uint_least16_t)value;
else if (field->data_size == sizeof(uint_least8_t))
clamped = *(uint_least8_t*)field->pData = (uint_least8_t)value;
else
PB_RETURN_ERROR(stream, "invalid data_size");
if (clamped != value)
PB_RETURN_ERROR(stream, "integer too large");
return true;
}
else
{
pb_uint64_t value;
pb_int64_t svalue;
pb_int64_t clamped;
if (PB_LTYPE(field->type) == PB_LTYPE_SVARINT)
{
if (!pb_decode_svarint(stream, &svalue))
return false;
}
else
{
if (!pb_decode_varint(stream, &value))
return false;
/* See issue 97: Google's C++ protobuf allows negative varint values to
* be cast as int32_t, instead of the int64_t that should be used when
* encoding. Nanopb versions before 0.2.5 had a bug in encoding. In order to
* not break decoding of such messages, we cast <=32 bit fields to
* int32_t first to get the sign correct.
*/
if (field->data_size == sizeof(pb_int64_t))
svalue = (pb_int64_t)value;
else
svalue = (int32_t)value;
}
/* Cast to the proper field size, while checking for overflows */
if (field->data_size == sizeof(pb_int64_t))
clamped = *(pb_int64_t*)field->pData = svalue;
else if (field->data_size == sizeof(int32_t))
clamped = *(int32_t*)field->pData = (int32_t)svalue;
else if (field->data_size == sizeof(int_least16_t))
clamped = *(int_least16_t*)field->pData = (int_least16_t)svalue;
else if (field->data_size == sizeof(int_least8_t))
clamped = *(int_least8_t*)field->pData = (int_least8_t)svalue;
else
PB_RETURN_ERROR(stream, "invalid data_size");
if (clamped != svalue)
PB_RETURN_ERROR(stream, "integer too large");
return true;
}
}
static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_iter_t *field)
{
uint32_t size;
size_t alloc_size;
pb_bytes_array_t *dest;
if (!pb_decode_varint32(stream, &size))
return false;
if (size > PB_SIZE_MAX)
PB_RETURN_ERROR(stream, "bytes overflow");
alloc_size = PB_BYTES_ARRAY_T_ALLOCSIZE(size);
if (size > alloc_size)
PB_RETURN_ERROR(stream, "size too large");
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
{
#ifndef PB_ENABLE_MALLOC
PB_RETURN_ERROR(stream, "no malloc support");
#else
if (stream->bytes_left < size)
PB_RETURN_ERROR(stream, "end-of-stream");
if (!allocate_field(stream, field->pData, alloc_size, 1))
return false;
dest = *(pb_bytes_array_t**)field->pData;
#endif
}
else
{
if (alloc_size > field->data_size)
PB_RETURN_ERROR(stream, "bytes overflow");
dest = (pb_bytes_array_t*)field->pData;
}
dest->size = (pb_size_t)size;
return pb_read(stream, dest->bytes, (size_t)size);
}
static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_iter_t *field)
{
uint32_t size;
size_t alloc_size;
pb_byte_t *dest = (pb_byte_t*)field->pData;
if (!pb_decode_varint32(stream, &size))
return false;
if (size == (uint32_t)-1)
PB_RETURN_ERROR(stream, "size too large");
/* Space for null terminator */
alloc_size = (size_t)(size + 1);
if (alloc_size < size)
PB_RETURN_ERROR(stream, "size too large");
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
{
#ifndef PB_ENABLE_MALLOC
PB_RETURN_ERROR(stream, "no malloc support");
#else
if (stream->bytes_left < size)
PB_RETURN_ERROR(stream, "end-of-stream");
if (!allocate_field(stream, field->pData, alloc_size, 1))
return false;
dest = *(pb_byte_t**)field->pData;
#endif
}
else
{
if (alloc_size > field->data_size)
PB_RETURN_ERROR(stream, "string overflow");
}
dest[size] = 0;
if (!pb_read(stream, dest, (size_t)size))
return false;
#ifdef PB_VALIDATE_UTF8
if (!pb_validate_utf8((const char*)dest))
PB_RETURN_ERROR(stream, "invalid utf8");
#endif
return true;
}
static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_iter_t *field)
{
bool status = true;
bool submsg_consumed = false;
pb_istream_t substream;
if (!pb_make_string_substream(stream, &substream))
return false;
if (field->submsg_desc == NULL)
PB_RETURN_ERROR(stream, "invalid field descriptor");
/* Submessages can have a separate message-level callback that is called
* before decoding the message. Typically it is used to set callback fields
* inside oneofs. */
if (PB_LTYPE(field->type) == PB_LTYPE_SUBMSG_W_CB && field->pSize != NULL)
{
/* Message callback is stored right before pSize. */
pb_callback_t *callback = (pb_callback_t*)field->pSize - 1;
if (callback->funcs.decode)
{
status = callback->funcs.decode(&substream, field, &callback->arg);
if (substream.bytes_left == 0)
{
submsg_consumed = true;
}
}
}
/* Now decode the submessage contents */
if (status && !submsg_consumed)
{
unsigned int flags = 0;
/* Static required/optional fields are already initialized by top-level
* pb_decode(), no need to initialize them again. */
if (PB_ATYPE(field->type) == PB_ATYPE_STATIC &&
PB_HTYPE(field->type) != PB_HTYPE_REPEATED)
{
flags = PB_DECODE_NOINIT;
}
status = pb_decode_inner(&substream, field->submsg_desc, field->pData, flags);
}
if (!pb_close_string_substream(stream, &substream))
return false;
return status;
}
static bool checkreturn pb_dec_fixed_length_bytes(pb_istream_t *stream, const pb_field_iter_t *field)
{
uint32_t size;
if (!pb_decode_varint32(stream, &size))
return false;
if (size > PB_SIZE_MAX)
PB_RETURN_ERROR(stream, "bytes overflow");
if (size == 0)
{
/* As a special case, treat empty bytes string as all zeros for fixed_length_bytes. */
memset(field->pData, 0, (size_t)field->data_size);
return true;
}
if (size != field->data_size)
PB_RETURN_ERROR(stream, "incorrect fixed length bytes size");
return pb_read(stream, (pb_byte_t*)field->pData, (size_t)field->data_size);
}
#ifdef PB_CONVERT_DOUBLE_FLOAT
bool pb_decode_double_as_float(pb_istream_t *stream, float *dest)
{
uint_least8_t sign;
int exponent;
uint32_t mantissa;
uint64_t value;
union { float f; uint32_t i; } out;
if (!pb_decode_fixed64(stream, &value))
return false;
/* Decompose input value */
sign = (uint_least8_t)((value >> 63) & 1);
exponent = (int)((value >> 52) & 0x7FF) - 1023;
mantissa = (value >> 28) & 0xFFFFFF; /* Highest 24 bits */
/* Figure if value is in range representable by floats. */
if (exponent == 1024)
{
/* Special value */
exponent = 128;
mantissa >>= 1;
}
else
{
if (exponent > 127)
{
/* Too large, convert to infinity */
exponent = 128;
mantissa = 0;
}
else if (exponent < -150)
{
/* Too small, convert to zero */
exponent = -127;
mantissa = 0;
}
else if (exponent < -126)
{
/* Denormalized */
mantissa |= 0x1000000;
mantissa >>= (-126 - exponent);
exponent = -127;
}
/* Round off mantissa */
mantissa = (mantissa + 1) >> 1;
/* Check if mantissa went over 2.0 */
if (mantissa & 0x800000)
{
exponent += 1;
mantissa &= 0x7FFFFF;
mantissa >>= 1;
}
}
/* Combine fields */
out.i = mantissa;
out.i |= (uint32_t)(exponent + 127) << 23;
out.i |= (uint32_t)sign << 31;
*dest = out.f;
return true;
}
#endif