feat: bind ZSTD_decompressionMargin (in-place decompression)#34
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Adds ZstdFrame.decompressionMargin(byte[] / MemorySegment): the extra room needed to decompress a frame in place, where the output buffer overlaps the compressed input at its tail. Size the output buffer at decompressedSize + margin, place the frame at its end, and decompress from that tail slice into the start — no second allocation. Supports multi-frame input. Binds ZSTD_decompressionMargin. The test proves it end to end: it actually decompresses in place through the single-pass ZstdDecompressCtx.decompress(dst, src) and recovers the original from one overlapping buffer. docs/supported.md: memory sizing 8 -> 9/14. CHANGELOG updated. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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What
ZstdFrame.decompressionMargin(byte[] / MemorySegment)— the extra room needed to decompress a frame in place, where the output buffer overlaps the compressed input at its tail. BindsZSTD_decompressionMargin.Usage: size the output buffer at
decompressedSize + margin, place the compressed frame(s) at its end, then decompress from that tail slice into the start — no second allocation. Supports multi-frame input. On-theme with the zero-copy story.Tests
ZstdFrameTest.DecompressionMargin— positive margin, segment parity, garbage rejected, and the key one: an actual in-place round-trip throughZstdDecompressCtx.decompress(dst, src)(single-passZSTD_decompressDCtx) recovering the original from one overlapping buffer. 236 tests green, checkstyle + javadoc clean.Note
Did not bind
ZSTD_decodingBufferSize_min— it only serves the buffer-less streaming API (ZSTD_decompressContinue), which isn't bound, so it's useless on its own.Docs
docs/supported.md: memory sizing 8 → 9/14.CHANGELOG.mdupdated.🤖 Generated with Claude Code