diff options
| -rw-r--r-- | pb_decode.c | 58 |
1 files changed, 40 insertions, 18 deletions
diff --git a/pb_decode.c b/pb_decode.c index 7c3407ce..51df32f8 100644 --- a/pb_decode.c +++ b/pb_decode.c @@ -107,37 +107,59 @@ pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize) static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest) { uint8_t byte; - int bitpos = 0; - *dest = 0; + uint32_t result; + + if (!pb_read(stream, &byte, 1)) + return false; - while (bitpos < 32 && pb_read(stream, &byte, 1)) + if (!(byte & 0x80)) { - *dest |= (uint32_t)(byte & 0x7F) << bitpos; - bitpos += 7; - - if (!(byte & 0x80)) - return true; + /* Quick case, 1 byte value */ + result = byte; } - - PB_RETURN_ERROR(stream, "varint overflow"); + else + { + /* Multibyte case */ + int bitpos = 7; + result = byte & 0x7F; + + do + { + if (bitpos >= 32) + PB_RETURN_ERROR(stream, "varint overflow"); + + if (!pb_read(stream, &byte, 1)) + return false; + + result |= (uint32_t)(byte & 0x7F) << bitpos; + bitpos += 7; + } while (byte & 0x80); + } + + *dest = result; + return true; } bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest) { uint8_t byte; int bitpos = 0; - *dest = 0; + uint64_t result = 0; - while (bitpos < 64 && pb_read(stream, &byte, 1)) + do { - *dest |= (uint64_t)(byte & 0x7F) << bitpos; - bitpos += 7; + if (bitpos >= 64) + PB_RETURN_ERROR(stream, "varint overflow"); - if (!(byte & 0x80)) - return true; - } + if (!pb_read(stream, &byte, 1)) + return false; + + result |= (uint64_t)(byte & 0x7F) << bitpos; + bitpos += 7; + } while (byte & 0x80); - PB_RETURN_ERROR(stream, "varint overflow"); + *dest = result; + return true; } bool checkreturn pb_skip_varint(pb_istream_t *stream) |