nova-compress

Compression codecs for Nova — deflate/gzip/zlib (pure Nova, RFC 1950/1951/1952) one-shot and streaming encode/decode with a bomb-cap (D334) against decompression bombs, plus CRC-32/Adler-32 checksums, plus brotli (RFC 7932) decode over a vendored C decoder.

Backend for brotli: google/brotli’s decoder, vendored as SOURCE at native/brotli/ (v1.2.0, decoder-only — dec/ + common/, the encoder is dropped) and compiled by a thin C shim (native/compress_shim.c) — pure C, no Rust/cargo required to build this package. brotlidec self-builds from the vendored source on first nova test/nova build via the generic [ffi] vendor_src_dirs build-and-cache mechanism (see native/brotli/VENDORED.md) — no manual vcpkg/system install step and no prebuilt binary checked into the repo (a manually dropped-in prebuilt lib under native/brotli/lib/ still works too and is used as-is, skipping the vendor build). Everything else (deflate, gzip, zlib, checksums) is pure Nova — no native dependency at all.

Extracted from the Nova monorepo’s std/encoding/compress into a standalone repository per Plan 205, following the native-module pattern nova-tls established for mbedTLS (Plan 193): .nv facade + .c shim + vendored C source, wired through [ffi], zero Rust. Public API is unchanged from std.encoding.compress — only the module path moved (std.encoding.compress.* -> compress.*).

Usage

import compress.{gzip_decode, gzip_encode, brotli_decode}

fn round_trip() -> Result[(), CompressError] {
    ro raw = "hello, nova".bytes()
    ro packed = gzip_encode(raw, level: 6)!!
    ro back = gzip_decode(packed, max_output: 1 << 20)!!  // bomb-cap
    back
}

Layout

nova-compress/
├── nova.toml              [package] name = "compress"; [lib] src = "src"; [ffi] native shim
├── native/
│   ├── compress_shim.c      libbrotlidec backend (compiled via [ffi] c_shims)
│   ├── compress_shim.h       C-side prototypes (Nova <-> C ABI contract)
│   └── brotli/                vendored brotli v1.2.0 SOURCE (decoder-only)
│       ├── dec/                  upstream c/dec/*.{c,h}
│       ├── common/                upstream c/common/*.{c,h} (minus dictionary.bin*)
│       ├── include/brotli/         public decoder-facing headers
│       ├── LICENSE                 brotli's own MIT license
│       └── VENDORED.md             vendoring provenance + rebuild/bump notes
└── src/
    ├── ffi.nv                extern "C" fn declarations against native/compress_shim.c
    ├── error.nv                CompressError (typed error surface)
    ├── deflate.nv / inflate.nv  pure-Nova DEFLATE (RFC 1951) encode/decode
    ├── gzip.nv / zlib.nv        pure-Nova framing (RFC 1952 / RFC 1950) over deflate/inflate
    ├── checksum.nv              CRC-32 / Adler-32
    ├── brotli.nv                brotli (RFC 7932) decode over the C shim
    ├── *_test.nv                peer tests (same-module, positive)
    └── neg/                     EXPECT_COMPILE_ERROR fixtures (standalone CUs)

Building standalone

Requires the Nova toolchain (nova CLI + clang). No Rust/cargo, no manual brotli install — brotlidec self-builds from the vendored source at native/brotli/ on first run (drop a prebuilt brotlidec lib under native/brotli/lib/ instead if you’d rather skip that one-time build).

# Boehm GC (mandatory Nova runtime dep) needs its own lib/include dirs —
# point NOVA_GC_LIB_DIR (+ optional NOVA_GC_INCLUDE_DIR) at a prebuilt
# bdwgc if it isn't reachable via the default vcpkg/system lookup.
export NOVA_GC_LIB_DIR=/path/to/vcpkg_installed/x64-windows-static/lib
export NOVA_GC_INCLUDE_DIR=/path/to/vcpkg_installed/x64-windows-static/include

# `nova` does not (yet) bundle/locate the standard library relative to the
# nova.exe install — a standalone package must point it at a Nova checkout's
# std/ via NOVA_STD_PATH:
export NOVA_STD_PATH=/path/to/nova/std

# Ditto for the compiler's own C runtime (compiler-codegen/nova_rt/ + the
# libuv submodule it needs):
export NOVA_CG_INCLUDE=/path/to/nova/compiler-codegen
export NOVA_RT_DIR=/path/to/nova/compiler-codegen/nova_rt

nova test src

License

Dual-licensed under MIT or Apache-2.0, at your option — same terms as the Nova compiler and standard library. The vendored brotli source under native/brotli/ carries its own upstream MIT license (native/brotli/LICENSE).