diff options
| -rw-r--r-- | pb_decode.c | 29 | ||||
| -rw-r--r-- | pb_decode.h | 4 |
2 files changed, 13 insertions, 20 deletions
diff --git a/pb_decode.c b/pb_decode.c index 48068325..9df4a894 100644 --- a/pb_decode.c +++ b/pb_decode.c @@ -185,22 +185,26 @@ static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire } } -/* Decode string length from stream and return a substream with limited length. - * Before disposing the substream, remember to copy the substream->state back - * to stream->state. - */ +/* Decode string length from stream and return a substream with limited length. */ +static bool substream_callback(pb_istream_t *stream, uint8_t *buf, size_t count) +{ + pb_istream_t *parent = (pb_istream_t*)stream->state; + return pb_read(parent, buf, count); +} + static bool checkreturn 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) + if (stream->bytes_left < size) return false; + substream->callback = &substream_callback; + substream->state = stream; substream->bytes_left = size; - stream->bytes_left -= size; + return true; } @@ -288,7 +292,6 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t && PB_LTYPE(iter->current->type) <= PB_LTYPE_LAST_PACKABLE) { /* Packed array */ - bool status; size_t *size = (size_t*)iter->pSize; pb_istream_t substream; if (!make_string_substream(stream, &substream)) @@ -301,9 +304,7 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t return false; (*size)++; } - status = (substream.bytes_left == 0); - stream->state = substream.state; - return status; + return (substream.bytes_left == 0); } else { @@ -337,7 +338,6 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t return false; } - stream->state = substream.state; return true; } else @@ -575,7 +575,6 @@ bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, vo bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest) { - bool status; pb_istream_t substream; if (!make_string_substream(stream, &substream)) @@ -584,7 +583,5 @@ bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field if (field->ptr == NULL) return false; - status = pb_decode(&substream, (pb_field_t*)field->ptr, dest); - stream->state = substream.state; - return status; + return pb_decode(&substream, (pb_field_t*)field->ptr, dest); } diff --git a/pb_decode.h b/pb_decode.h index 192326eb..9cc67e8e 100644 --- a/pb_decode.h +++ b/pb_decode.h @@ -23,10 +23,6 @@ * * 3) You can use state to store your own data (e.g. buffer pointer), * and rely on pb_read to verify that no-body reads past bytes_left. - * - * 4) Your callback may be used with substreams, in which case bytes_left - * is different than from the main stream. Don't use bytes_left to compute - * any pointers. */ struct _pb_istream_t { |