bool pb_field_iter_next(pb_field_iter_t *iter)
{
const pb_field_t *prev_field = iter->pos;
if (prev_field->tag == 0)
{
/* Handle empty message types, where the first field is already the terminator.
* In other cases, the iter->pos never points to the terminator. */
return false;
}
iter->pos++;
if (iter->pos->tag == 0)
{
/* Wrapped back to beginning, reinitialize */
(void)pb_field_iter_begin(iter, iter->start, iter->dest_struct);
return false;
}
else
{
/* Increment the pointers based on previous field size */
size_t prev_size = prev_field->data_size;
if (PB_HTYPE(prev_field->type) == PB_HTYPE_ONEOF &&
PB_HTYPE(iter->pos->type) == PB_HTYPE_ONEOF)
{
/* Don't advance pointers inside unions */
prev_size = 0;
iter->pData = (char*)iter->pData - prev_field->data_offset;
}
else if (PB_ATYPE(prev_field->type) == PB_ATYPE_STATIC &&
PB_HTYPE(prev_field->type) == PB_HTYPE_REPEATED)
{
/* In static arrays, the data_size tells the size of a single entry and
* array_size is the number of entries */
prev_size *= prev_field->array_size;
}
else if (PB_ATYPE(prev_field->type) == PB_ATYPE_POINTER)
{
/* Pointer fields always have a constant size in the main structure.
* The data_size only applies to the dynamically allocated area. */
prev_size = sizeof(void*);
}
if (PB_HTYPE(prev_field->type) == PB_HTYPE_REQUIRED)
{
/* Count the required fields, in order to check their presence in the
* decoder. */
iter->required_field_index++;
}
iter->pData = (char*)iter->pData + prev_size + iter->pos->data_offset;
iter->pSize = (char*)iter->pData + iter->pos->size_offset;
return true;
}
}
static bool checkreturn pb_enc_string(pb_ostream_t *stream, const pb_field_t *field, const void *src)
{
size_t size = 0;
size_t max_size = field->data_size;
const char *p = (const char*)src;
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
max_size = (size_t)-1;
if (src == NULL)
{
size = 0; /* Threat null pointer as an empty string */
}
else
{
/* strnlen() is not always available, so just use a loop */
while (size < max_size && *p != '\0')
{
size++;
p++;
}
}
return pb_encode_string(stream, (const uint8_t*)src, size);
}
static bool pb_field_next(pb_field_iterator_t *iter)
{
bool notwrapped = true;
size_t prev_size = iter->current->data_size;
if (PB_ATYPE(iter->current->type) == PB_ATYPE_STATIC &&
PB_HTYPE(iter->current->type) == PB_HTYPE_REPEATED)
{
prev_size *= iter->current->array_size;
}
if (PB_HTYPE(iter->current->type) == PB_HTYPE_REQUIRED)
iter->required_field_index++;
iter->current++;
iter->field_index++;
if (iter->current->tag == 0)
{
iter->current = iter->start;
iter->field_index = 0;
iter->required_field_index = 0;
iter->pData = iter->dest_struct;
prev_size = 0;
notwrapped = false;
}
iter->pData = (char*)iter->pData + prev_size + iter->current->data_offset;
iter->pSize = (char*)iter->pData + iter->current->size_offset;
return notwrapped;
}
/* Initialize message fields to default values, recursively */
static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct)
{
pb_field_iterator_t iter;
pb_field_init(&iter, fields, dest_struct);
/* Initialize size/has fields and apply default values */
do
{
pb_type_t type;
type = iter.current->type;
if (iter.current->tag == 0)
continue;
if (PB_ATYPE(type) == PB_ATYPE_STATIC)
{
/* Initialize the size field for optional/repeated fields to 0. */
if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL)
{
*(bool*)iter.pSize = false;
}
else if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
{
*(size_t*)iter.pSize = 0;
continue; /* Array is empty, no need to initialize contents */
}
/* Initialize field contents to default value */
if (PB_LTYPE(iter.current->type) == PB_LTYPE_SUBMESSAGE)
{
pb_message_set_to_defaults((const pb_field_t *) iter.current->ptr, iter.pData);
}
else if (iter.current->ptr != NULL)
{
memcpy(iter.pData, iter.current->ptr, iter.current->data_size);
}
else
{
memset(iter.pData, 0, iter.current->data_size);
}
}
else if (PB_ATYPE(type) == PB_ATYPE_CALLBACK)
{
continue; /* Don't overwrite callback */
}
} while (pb_field_next(&iter));
}
/* Encode a field with static or pointer allocation, i.e. one whose data
* is available to the encoder directly. */
static bool checkreturn encode_basic_field(pb_ostream_t *stream,
const pb_field_t *field, const void *pData)
{
pb_encoder_t func;
const void *pSize;
bool implicit_has = true;
func = PB_ENCODERS[PB_LTYPE(field->type)];
if (field->size_offset)
pSize = (const char*)pData + field->size_offset;
else
pSize = &implicit_has;
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
{
/* pData is a pointer to the field, which contains pointer to
* the data. If the 2nd pointer is NULL, it is interpreted as if
* the has_field was false.
*/
pData = *(const void* const*)pData;
implicit_has = (pData != NULL);
}
switch (PB_HTYPE(field->type))
{
case PB_HTYPE_REQUIRED:
if (!pData)
PB_RETURN_ERROR(stream, "missing required field");
if (!pb_encode_tag_for_field(stream, field))
return false;
if (!func(stream, field, pData))
return false;
break;
case PB_HTYPE_OPTIONAL:
if (*(const bool*)pSize)
{
if (!pb_encode_tag_for_field(stream, field))
return false;
if (!func(stream, field, pData))
return false;
}
break;
case PB_HTYPE_REPEATED:
if (!encode_array(stream, field, pData, *(const size_t*)pSize, func))
return false;
break;
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
return true;
}
static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iterator_t *iter)
{
switch (PB_ATYPE(iter->current->type))
{
case PB_ATYPE_STATIC:
return decode_static_field(stream, wire_type, iter);
case PB_ATYPE_CALLBACK:
return decode_callback_field(stream, wire_type, iter);
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
}
/* Encode a single field of any callback or static type. */
static bool checkreturn encode_field(pb_ostream_t *stream,
const pb_field_t *field, const void *pData)
{
switch (PB_ATYPE(field->type))
{
case PB_ATYPE_STATIC:
return encode_static_field(stream, field, pData);
case PB_ATYPE_CALLBACK:
return encode_callback_field(stream, field, pData);
default:
PB_RETURN_ERROR(stream, "invalid field type");
}
}
/* Default handler for extension fields. Expects to have a pb_field_t
* pointer in the extension->type->arg field. */
static bool checkreturn default_extension_encoder(pb_ostream_t *stream,
const pb_extension_t *extension)
{
const pb_field_t *field = (const pb_field_t*)extension->type->arg;
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
{
/* For pointer extensions, the pointer is stored directly
* in the extension structure. This avoids having an extra
* indirection. */
return encode_field(stream, field, &extension->dest);
}
else
{
return encode_field(stream, field, extension->dest);
}
}
static bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src)
{
const pb_bytes_array_t *bytes = (const pb_bytes_array_t*)src;
if (src == NULL)
{
/* Threat null pointer as an empty bytes field */
return pb_encode_string(stream, NULL, 0);
}
if (PB_ATYPE(field->type) == PB_ATYPE_STATIC &&
PB_BYTES_ARRAY_T_ALLOCSIZE(bytes->size) > field->data_size)
{
PB_RETURN_ERROR(stream, "bytes size exceeded");
}
return pb_encode_string(stream, bytes->bytes, bytes->size);
}
bool checkreturn pb_encode(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)
{
const pb_field_t *field = fields;
const void *pData = src_struct;
size_t prev_size = 0;
while (field->tag != 0)
{
pData = (const char*)pData + prev_size + field->data_offset;
prev_size = field->data_size;
/* Special case for static arrays */
if (PB_ATYPE(field->type) == PB_ATYPE_STATIC &&
PB_HTYPE(field->type) == PB_HTYPE_REPEATED)
{
prev_size *= field->array_size;
}
if (PB_LTYPE(field->type) == PB_LTYPE_EXTENSION)
{
/* Special case for the extension field placeholder */
if (!encode_extension_field(stream, field, pData))
return false;
}
else
{
/* Regular field */
if (!encode_field(stream, field, pData))
return false;
}
field++;
}
return true;
}
/* Encode a static array. Handles the size calculations and possible packing. */
static bool checkreturn encode_array(pb_ostream_t *stream, const pb_field_t *field,
const void *pData, size_t count, pb_encoder_t func)
{
size_t i;
const void *p;
size_t size;
if (count == 0)
return true;
if (PB_ATYPE(field->type) != PB_ATYPE_POINTER && count > field->array_size)
PB_RETURN_ERROR(stream, "array max size exceeded");
/* We always pack arrays if the datatype allows it. */
if (PB_LTYPE(field->type) <= PB_LTYPE_LAST_PACKABLE)
{
if (!pb_encode_tag(stream, PB_WT_STRING, field->tag))
return false;
/* Determine the total size of packed array. */
if (PB_LTYPE(field->type) == PB_LTYPE_FIXED32)
{
size = 4 * count;
}
else if (PB_LTYPE(field->type) == PB_LTYPE_FIXED64)
{
size = 8 * count;
}
else
{
pb_ostream_t sizestream = PB_OSTREAM_SIZING;
p = pData;
for (i = 0; i < count; i++)
{
if (!func(&sizestream, field, p))
return false;
p = (const char*)p + field->data_size;
}
size = sizestream.bytes_written;
}
if (!pb_encode_varint(stream, (uint64_t)size))
return false;
if (stream->callback == NULL)
return pb_write(stream, NULL, size); /* Just sizing.. */
/* Write the data */
p = pData;
for (i = 0; i < count; i++)
{
if (!func(stream, field, p))
return false;
p = (const char*)p + field->data_size;
}
}
else
{
p = pData;
for (i = 0; i < count; i++)
{
if (!pb_encode_tag_for_field(stream, field))
return false;
/* Normally the data is stored directly in the array entries, but
* for pointer-type string and bytes fields, the array entries are
* actually pointers themselves also. So we have to dereference once
* more to get to the actual data. */
if (PB_ATYPE(field->type) == PB_ATYPE_POINTER &&
(PB_LTYPE(field->type) == PB_LTYPE_STRING ||
PB_LTYPE(field->type) == PB_LTYPE_BYTES))
{
if (!func(stream, field, *(const void* const*)p))
return false;
}
else
{
if (!func(stream, field, p))
return false;
}
p = (const char*)p + field->data_size;
}
}
return true;
}
