kvrocks' BITCOUNT result is different from Redis about kvrocks HOT 13 CLOSED

#2074

Found BitmapString also has this problem 😅 Let me take time to fix it

Oh, it's an expected behavior

from kvrocks.

  if (start < 0 || stop <= 0 || start >= stop) return rocksdb::Status::OK();

The point maybe the condition above...

from kvrocks.

if (start < 0) start += static_cast<int64_t>(metadata.size) + 1;
if (stop < 0) stop += static_cast<int64_t>(metadata.size) + 1;
if (stop > static_cast<int64_t>(metadata.size)) stop = static_cast<int64_t>(metadata.size);
if (start < 0 || stop <= 0 || start >= stop) return rocksdb::Status::OK();

I think the code is confused, what is themetadata.sizemeans？ the used bytes of bitmap，why should +1 ？

from kvrocks.

what is themetadata.sizemeans

Means the "extended" bit size. e.g.:

set bit 100 1
--> length = 100
set bit 99 1
--> length = 99
set bit 101 1
--> length = 101

the used bytes of bitmap，why should +1

You can edit it as you'd like 🤔

from kvrocks.

@mapleFU I do a test, it it not work like you said:
set bit 100 1
--> length = 100
but: length = 13 😄

from kvrocks.

Yeah, it's bytesize, should contain a mod 8:

  uint32_t byte_index = (offset / 8) % kBitmapSegmentBytes;
  uint64_t used_size = index + byte_index + 1;
  uint64_t bitmap_size = std::max(used_size, metadata.size);

from kvrocks.

Maybe this is the same reason with #1212 (comment)

from kvrocks.

@kay011 would you like fixing this? If not I'll do a quick fixing

from kvrocks.

@kay011 would you like fixing this? If not I'll do a quick fixing

you can do it, I will merge your code in my other feature

from kvrocks.

I'm trying to fix it here: #2069

from kvrocks.

@mapleFU BITPOS command may be have the same problem, please check~

from kvrocks.

Sigh, I've checked and also fixed that

from kvrocks.

closed by #2069

from kvrocks.