gazagnaire.org
When exactly header_size (7) bytes remain in a block, avail = 0 causes a 0-length fragment → Invalid_argument("empty record"). Fix: < → <= to pad and skip to the next block. By Claude
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round #0
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lib/wal.ml
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lib/wal.ml
···
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else
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(* Space left in current block *)
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let block_remaining = block_size - t.block_offset in
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if block_remaining < header_size then begin
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if block_remaining <= header_size then begin
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(* Not enough space for header, pad and move to next block *)
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let padding = String.make block_remaining '\x00' in
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Eio.File.pwrite_all t.file ~file_offset:t.file_offset
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Fix off-by-one in WAL block boundary check
When exactly `header_size` (7) bytes remain in a block, there is no
space for data after the header. The old check `block_remaining <
header_size` let this case fall through to `write_fragments`, which
computed `avail = block_remaining - header_size = 0` and tried to
create a 0-length fragment. This triggered the `encode_record`
`Invalid_argument("empty record")` error.
Change `<` to `<=` so that when `block_remaining == header_size`, we
pad and move to the next block instead.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
no conflicts, ready to merge