nim-codex/dagger/blockset.nim

63 lines
1.6 KiB
Nim

## Nim-Dagger
## Copyright (c) 2021 Status Research & Development GmbH
## Licensed under either of
## * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
## * MIT license ([LICENSE-MIT](LICENSE-MIT))
## at your option.
## This file may not be copied, modified, or distributed except according to
## those terms.
{.push raises: [Defect].}
import pkg/libp2p
import pkg/questionable
import pkg/questionable/results
import ./blockstream
export blockstream
type
BlockSetRef* = ref object of BlockStreamRef
stream*: BlockStreamRef
hcodec*: MultiCodec
proc hashBytes*(mh: MultiHash): seq[byte] =
mh.data.buffer[mh.dpos..(mh.dpos + mh.size - 1)]
proc hashBytes*(b: Block): seq[byte] =
if mh =? b.cid.mhash:
return mh.hashBytes()
method nextBlock*(d: BlockSetRef): ?!Block =
d.stream.nextBlock()
proc treeHash*(d: BlockSetRef): ?!MultiHash =
var
stack: seq[seq[byte]]
while true:
let (blk1, blk2) = (d.nextBlock().option, d.nextBlock().option)
if blk1.isNone and blk2.isNone and stack.len == 1:
let res = MultiHash.digest($d.hcodec, stack[0])
if mh =? res:
return success mh
return failure($res.error)
if blk1.isSome: stack.add((!blk1).hashBytes())
if blk2.isSome: stack.add((!blk2).hashBytes())
while stack.len > 1:
let (b1, b2) = (stack.pop(), stack.pop())
let res = MultiHash.digest($d.hcodec, b1 & b2)
if mh =? res:
stack.add(mh.hashBytes())
else:
return failure($res.error)
func new*(
T: type BlockSetRef,
stream: BlockStreamRef,
hcodec: MultiCodec = multiCodec("sha2-256")): T =
T(stream: stream, hcodec: hcodec)