def next.body.valid

mylsm-lsm-store@0.6.0.1 · src/scan/ByteBlockReader.bend:1339

import Base
import mylsm-lsm-store@0.6.0.1/src/Fs.bend as Fs
import bend-kit-bytes@0.3.2.0/bytes.bend as Bytes

1339def next.body.valid(
1340  file: File,
1341  state: State,
1342  block_header: Bytes.Bytes,
1343  +used: Nat,
1344  +payload_length: U32,
1345  valid: Bool
1346) -> IO(Result<&1, &1, U32 & String, Step>):
1347  match valid:
1348    case False{}:
1349      close.failed(file, corruption("byte SST block exceeds file bounds"))
1350    case True{}:
1351      do IO<Result<&1, &1, U32 & String, Step>>:
1352        raw : File & Result<&1, &1, U32 & String, Bytes.Bytes> <-
1353          Fs.read_at(file,
1354            U32.from_nat(Nat.add(Nat.add(20n, used), 8n)),
1355            U32.add(payload_length, 32))
1356        next.body.result(BodyContext{state, block_header, payload_length},
1357          read_at.exact.pair(U32.add(payload_length, 32), raw))