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;
}
}
/* This function is the core of the union encoding process. It handles
* the top-level pb_field_t array manually, in order to encode a correct
* field tag before the message. The pointer to MsgType_fields array is
* used as an unique identifier for the message type.
*/
bool encode_unionmessage(pb_ostream_t *stream, const pb_msgdesc_t *messagetype, void *message)
{
pb_field_iter_t iter;
if (!pb_field_iter_begin(&iter, UnionMessage_fields, message))
return false;
do
{
if (iter.submsg_desc == messagetype)
{
/* This is our field, encode the message using it. */
if (!pb_encode_tag_for_field(stream, &iter))
return false;
return pb_encode_submessage(stream, messagetype, message);
}
} while (pb_field_iter_next(&iter));
/* Didn't find the field for messagetype */
return false;
}
bool checkreturn pb_encode(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)
{
pb_field_iter_t iter;
if (!pb_field_iter_begin(&iter, fields, remove_const(src_struct)))
return true; /* Empty message type */
do {
if (PB_LTYPE(iter.pos->type) == PB_LTYPE_EXTENSION)
{
/* Special case for the extension field placeholder */
if (!encode_extension_field(stream, iter.pos, iter.pData))
return false;
}
else
{
/* Regular field */
if (!encode_field(stream, iter.pos, iter.pData))
return false;
}
} while (pb_field_iter_next(&iter));
return true;
}
