Pure Go implementation of LZO1X compression and decompression, compatible with lzo1x_decompress_safe-style streams.
The current encoder/decoder cores were rewritten using permissive AxioDL/lzokay (MIT) references.

go get github.com/woozymasta/lzo

opts may be nil (default level 1). Level 0 or 1 = fast LZO1X-1; 2–9 = LZO1X-999.

import "github.com/woozymasta/lzo"

// Default (level 1, fast)
compressed, err := lzo.Compress(data, nil)

// Best ratio (level 9)
compressed, err := lzo.Compress(data, &lzo.CompressOptions{Level: 9})

// Direct LZO1X-999 API
compressed, err := lzo.Compress1X999(data)       // level 9
compressed, err := lzo.Compress1X999Level(data, 5) // level 5

OutLen (expected decompressed size) is required for buffer allocation and safety.

opts := lzo.DefaultDecompressOptions(expectedLen)
out, err := lzo.Decompress(compressed, opts)

Decompress returns out[:n], so resulting length can be less than OutLen when the stream terminator is reached earlier.

Need consumed input bytes for concatenated blocks:

opts := lzo.DefaultDecompressOptions(expectedLen)
out, nRead, err := lzo.DecompressN(compressed, opts)
_ = out
compressed = compressed[nRead:]

Reuse caller-owned output buffer (no per-call output allocation):

dst := make([]byte, expectedLen)
out, err := lzo.DecompressInto(compressed, dst)
out, nRead, err := lzo.DecompressNInto(compressed, dst)
_ = out
compressed = compressed[nRead:]

From an io.Reader (e.g. stream with known decompressed size):

out, err := lzo.DecompressFromReader(r, lzo.DefaultDecompressOptions(expectedLen))

Optional limit on input size:

opts := lzo.DefaultDecompressOptions(expectedLen)
opts.MaxInputSize = 1 << 20
out, err := lzo.DecompressFromReader(r, opts)

Higher levels (e.g. 9) give smaller output and are slower.

• Output is LZO1X with match types M1–M4; stream ends with the standard terminator bytes 0x11 0x00 0x00.
• Decompression is compatible with streams produced by lzo1x_decompress_safe-style encoders.

make test
make bench

Benchmarks cover multiple inputs (small text, pattern, byte cycle) and levels 1, 5, 9 for both compress and decompress.