Dispatch ordinary dictionary-free ZSTD_compress2 calls through the Rust frame
compressor while retaining the original C implementation for advanced
contexts. Prepare the C workspace first so allocation downsizing and
static-context limits remain observable.
Mark successful Rust frames so a following one-shot
ZSTD_compressStream2(..., ZSTD_e_end) call uses the same output path. Other
streaming directives and advanced parameters remain on the C implementation.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path
rust/Cargo.toml --no-default-features --features compression
zstd_compress::tests
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path
rust/Cargo.toml --no-default-features --features compression -- -D warnings
- cargo +nightly fmt --manifest-path rust/Cargo.toml -- --check
- make -B -C tests fuzzer
- ./tests/fuzzer -t114 -i1000 --no-big-tests -s1
The basic fuzzer run now reaches the existing Rust one-shot compression-ratio
limit at test 113; the new stateful reuse tests pass before that point.
Move ZSTD_compressCCtx() onto the Rust frame-compression path while
retaining only the C-owned reset needed for its private context layout.
The simple API ignores advanced context parameters by contract, so the
Rust entry point can share the one-shot implementation after reset.
Preserve valid frames when the Rust superblock leaf declines a compressed
block by emitting a raw block instead. Match the fast-strategy literal
policy for negative levels so compatibility behavior remains intact.
Streaming, stateful ZSTD_compress2(), and multithreaded context
orchestration remain C-owned for a later slice. The full fuzzer currently
reaches an existing compress2() superblock-expansion failure after these
simple-API checks; that stateful path is intentionally out of scope here.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml --no-default-features
--features compression zstd_compress::tests
- cargo clippy --manifest-path rust/Cargo.toml -- -D warnings
(library, benches, and tests)
- cargo +nightly fmt --manifest-path rust/Cargo.toml -- --check
- make -B -C programs zstd V=1
- make -B -C examples multiple_simple_compression
- ./multiple_simple_compression README.md ../rust/README.md
Move the frozen v0.7 decoder, dictionary handling, bufferless streaming,
and buffered streaming implementation into the Rust legacy module. Keep
the historical C translation unit as a declaration-only ABI shim so the
existing C callers and build selection remain unchanged.
The port preserves the v0.7 entropy and frame boundaries, while fixing the
Rust-side literal-tail bookkeeping and making buffered header loading revisit
the complete frame header before sizing its rolling buffers.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml --no-default-features --features decompression,legacy-v07 legacy::zstd_v07::tests
- cargo clippy --manifest-path rust/Cargo.toml -- -D warnings
- make -B -C programs zstd V=1
- decode a v0.7.5 fixture and compare its 200000-byte output
- make -C tests check V=1
Replace the v0.5 and v0.6 legacy decoder translation units with Rust modules
and keep only narrow C registration shims for the public legacy dispatch ABI.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/Cargo.toml --features compression,decompression,dict-builder,legacy-v05,legacy-v06,legacy-v07
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/Cargo.toml --all-targets --features compression,decompression,dict-builder,legacy-v05,legacy-v06,legacy-v07 -- -D warnings
- make -C tests check V=1
Delay the legacy dictionary segment copy until the effective content size is
known, preventing writes beyond the caller-provided dictionary capacity.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/cli/Cargo.toml
- make -C tests check V=1
Move filename tables, file-list expansion, core-count helpers, statistics,
and dictionary sample loading behind Rust implementations while retaining
the narrow C ABI used by the CLI.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/cli/Cargo.toml
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- make -B -C programs zstd V=1
- make -C tests check V=1
Add Rust parsing and dispatch for the default, Cover, FastCover, and legacy
dictionary-training modes, including their parameter validation, output
defaults, and help text. Keep file loading behind the existing narrow dibio
bridge while the dictionary algorithms are supplied by the Rust library.
Test Plan:
- rustfmt +nightly --check --edition 2021 rust/src/zstd_cli.rs
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/cli/Cargo.toml
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- git diff --cached --check
Move the frozen v0.4 frame, entropy, streaming, and dictionary decoder
implementation to Rust while retaining the C translation unit as an ABI
anchor. Register the decoder behind the matching legacy feature and keep its
historical behavior isolated from newer formats.
Test Plan:
- rustfmt +nightly --check --edition 2021 rust/src/legacy/zstd_v04.rs rust/src/legacy/mod.rs
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/Cargo.toml --no-default-features --features decompression,legacy-v04 legacy::zstd_v04
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/Cargo.toml --all-targets --no-default-features --features decompression,legacy-v04 -- -D warnings
- C/Rust v0.4 ABI and decompression build checks
- git diff --cached --check
Move FastCover parameter validation, corpus preparation, optimization, and
dictionary training into Rust. Retain the C source as a static-linking ABI
anchor and register the implementation with the compression dictionary-builder
feature set.
Test Plan:
- rustfmt +nightly --check --edition 2021 rust/src/dict_builder_fastcover.rs rust/src/lib.rs
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/Cargo.toml --all-targets --no-default-features --features compression,dict-builder -- -D warnings
- FastCover focused Rust tests and deterministic C-reference harness
- git diff --cached --check
Move fileio preference and context allocation, defaults, setters, and small
query helpers into Rust while keeping the actual file operations in C. Keep
the C structs and ABI declarations as anchors, and make the CLI build track
the new Rust source.
Test Plan:
- rustfmt +nightly --check --edition 2021 rust/src/fileio_prefs.rs rust/cli/src/lib.rs
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/cli/Cargo.toml
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- git diff --cached --check
Move the public ZDICT helpers, legacy trainer, dictionary finalization,
entropy-table construction, and supporting dictionary logic into Rust. Keep
the C translation unit as an ABI anchor and register the Rust module only
when compression and dictionary-builder features are enabled.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path rust/Cargo.toml dict_builder_zdict
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
- rustfmt +nightly --check --edition 2021 rust/src/dict_builder_zdict.rs rust/src/lib.rs
- git diff --cached --check
Move the frozen v0.3 frame decoder, entropy tables, and streaming context
state into a feature-gated Rust module. Keep the historical C translation
unit as an ABI shim so existing C callers retain the opaque context and
error-code contracts while v0.4 and newer decoders remain unchanged.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path
rust/Cargo.toml --no-default-features --features legacy-v01,legacy-v02,
legacy-v03
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path
rust/Cargo.toml --no-default-features --features compression,decompression,
dict-builder,legacy-v01,legacy-v02,legacy-v03
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path
rust/Cargo.toml --all-targets --no-default-features --features
compression,decompression,dict-builder,legacy-v01,legacy-v02,legacy-v03
-- -D warnings
- make -B -C lib libzstd.a ZSTD_LEGACY_SUPPORT=3 V=1
- git diff --cached --check
Move the reusable buffer and compression-context pools behind a Rust
implementation with a narrow C ABI adapter. The scheduler, job table, serial
LDM state, and stream orchestration remain in C until their private layouts
are ported.
Keep context types opaque across Rust modules so the pool bridge does not
depend on private C layout declarations. This also keeps the existing custom
allocator and pool replacement contracts intact.
Test Plan:
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo clippy --manifest-path
rust/Cargo.toml --all-targets -- -D warnings
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= cargo test --manifest-path
rust/Cargo.toml zstdmt_compress
- make -B -C lib lib-mt
- git diff --cached --check
Implement the Rust frontend's --show-default-cparams path, including source
and dictionary size discovery, strategy labels, verbose --zstd parameter
reporting, and the decompression-mode diagnostic. Keep the C parameter API
as the source of the selected values so the CLI remains aligned with the
active compression build.
Test Plan:
- cargo test --manifest-path rust/cli/Cargo.toml
- cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- rustfmt +nightly --edition 2021 rust/src/zstd_cli.rs
- git diff --check
Depends-on: Rust CLI parser, file-selection, and C fileio bridge ports
Move COVER training, frequency mapping, segment selection, optimization,
dictionary shrinking, and best-candidate synchronization into Rust. The
remaining C translation unit is an ABI shim, while the public ZDICT and COVER
symbols stay available to the existing C dictionary-builder callers.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml dict_builder_cover
- cargo check --manifest-path rust/Cargo.toml --no-default-features --features compression,decompression,dict-builder
- cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
- make -B -C lib libzstd.a V=1
- git diff --check
Depends-on: Rust compression, entropy, and dictionary-finalization leaves
Move the public ZBUFF compatibility layer into the Rust static archive while
keeping stream contexts opaque and forwarding to the current ZSTD streaming
APIs. The deprecated C translation units are now declaration-only shims, so
the compatibility symbols work in compression-only and decompression-only
feature builds without duplicating private context layouts.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml
- cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
- cargo +nightly fmt --manifest-path rust/Cargo.toml -- --check
- make -B -C lib libzstd.a ZSTD_LIB_DEPRECATED=1 V=1
- C ZBUFF compress/decompress smoke test against the rebuilt static archive
Depends-on: Rust compression and decompression streaming ABI ports
Move the binary-tree optimal and ultra block parsers into Rust with a narrow
C projection of match-state, sequence-store, and entropy-table fields. Keep
the established C entry points as wrappers, and avoid reading uninitialized
entropy costs during dictionary tree updates.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml
- cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
- cargo +nightly fmt --manifest-path rust/Cargo.toml --all -- --check
- make -B -C tests test-zstream V=1
- git diff --check
Refs: rust/src/zstd_opt.rs, lib/compress/zstd_opt.c
Translate the frozen v0.2 frame, entropy, block, frame-size, and streaming
decoder paths to Rust while preserving the opaque C context ABI. Replace the
3465-line historical C implementation with a declaration-only shim and enable
the Rust module for the legacy-v02 Cargo feature.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml --no-default-features --features compression,decompression,dict-builder,legacy-v02
- make -B -C lib libzstd.a ZSTD_LEGACY_SUPPORT=2 V=1
- git diff --check
Refs: rust/src/legacy/zstd_v02.rs, lib/legacy/zstd_v02.c
Implement ZSTD_compress in Rust using the migrated parameter, match-finder,
sequence, frame, and superblock leaves. Keep the private context and streaming
entry points C-backed until their configuration-dependent context projection is
ported, and remove only the duplicate C one-shot definition.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml
- cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
- cargo +nightly fmt --manifest-path rust/Cargo.toml --all -- --check
- make -B -C tests test-rust-lib-smoke V=1
- git diff --check
Refs: rust/src/zstd_compress.rs, lib/compress/zstd_compress.c
Set the C file-I/O patch-from flag explicitly when the Rust frontend creates
preferences. The parser still rejects the unported option, but this keeps the
backend in ordinary dictionary mode instead of reading an unspecified field.
Test Plan:
- cargo test --manifest-path rust/cli/Cargo.toml --all-features
- cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- git diff --check
Refs: rust/src/zstd_cli.rs, programs/fileio.c
Move recursive expansion, file-list inputs, output-directory dispatch, and
frame listing into the Rust command-line frontend while keeping directory
traversal and file I/O in the existing C helpers. Preserve the unsigned fast
compression-level parsing and add focused parser coverage for the new modes.
Test Plan:
- cargo test --manifest-path rust/cli/Cargo.toml --all-features
- cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- git diff --check
Refs: rust/src/zstd_cli.rs, programs/util.c, programs/fileio.c
The C command-line parser accepts short-form levels through an unsigned
32-bit conversion before storing them in the signed compression-level field.
The Rust parser used signed parsing for both ordinary levels and --fast,
rejecting 4294967295 even though it represents the valid fast level -1.
Mirror the conversion and retain the fast-level clamp for the attached form.
Test Plan:
- cargo test --manifest-path rust/cli/Cargo.toml --all-features
- cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
- make -C programs zstd
- ./programs/zstd --fast -4294967295 tests/playTests.sh -o /tmp/zstd-fast-test
- ./programs/zstd --fast=4294967295 tests/playTests.sh -o /tmp/zstd-fast-test
Refs: tests/playTests.sh maximum fast-level cases
Move LOREM_genBlock and LOREM_genBuffer into the Rust CLI helper archive,
preserving the frozen word distribution, seeded sentence and paragraph layout,
tail filling, and C-compatible buffer ABI. Use per-call state so generation is
reentrant without changing the generated bytes.
Focused tests cover C reference vectors, distribution construction,
determinism, zero-sized null buffers, tiny tail-filled buffers, and continued
nonzero-fill generation.
Test Plan:
- cargo test --manifest-path rust/cli/Cargo.toml --no-default-features lorem::tests
- cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings
Refs: programs/lorem.c compatibility port
Move RDG_genBuffer and RDG_genStdout into the Rust CLI helper archive while
preserving the C generator's random-draw order, fixed-point literal table,
sparse-data path, sliding dictionary, and public ABI. Keep a zero-length
buffer a valid no-op even when its pointer is null.
The focused tests include C reference vectors, sparse and pure-noise inputs,
custom literal probabilities, reproducibility, and the null zero-length case.
Test Plan:
- cargo test --manifest-path rust/cli/Cargo.toml --no-default-features datagen::tests
- cargo test --manifest-path rust/cli/Cargo.toml --all-features
Refs: programs/datagen.c compatibility port
The compression round-trip tests built an X1 decode table unconditionally.
That violated the X2 decoder contract when the HUF force feature was enabled
and triggered the production debug assertion instead of testing the selected
configuration. Build the table with the selected X1/X2 reader and reserve the
corresponding table capacity.
Test Plan:
- cargo test --manifest-path rust/Cargo.toml
- cargo test --manifest-path rust/Cargo.toml --no-default-features --features compression,decompression,dict-builder,huf-force-decompress-x1,legacy-v01,legacy-v02,legacy-v03,legacy-v04,legacy-v05,legacy-v06,legacy-v07
- cargo test --manifest-path rust/Cargo.toml --no-default-features --features compression,decompression,dict-builder,huf-force-decompress-x2,legacy-v01,legacy-v02,legacy-v03,legacy-v04,legacy-v05,legacy-v06,legacy-v07
- cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
Refs: HUF force-mode build matrix
Continue the incremental zstd_compress.c migration with its sequence
statistics and seqStore entropy-compression layer. The following now
live in rust/src/zstd_compress_stats.rs:
- ZSTD_seqToCodes(), exported under its original name because the C
dictionary builder (zdict.c) and decodecorpus link against it,
- ZSTD_buildSequencesStatistics() and its dummy variant, whose result
struct no longer crosses the language boundary,
- ZSTD_entropyCompressSeqStore_internal(), _wExtLitBuffer(), and
ZSTD_entropyCompressSeqStore(),
- ZSTD_buildBlockEntropyStats() with its literals/sequences helpers,
- ZSTD_copyBlockSequences() and the ZSTD_updateRep() rules it shares
with the superblock writer.
Boundary: ZSTD_CCtx and ZSTD_CCtx_params stay private to C. These
paths read exactly two parameter fields, so the C shims keep the
original static/exported function names and forward the strategy and
ZSTD_literalsCompressionIsDisabled() as int scalars alongside the
seqStore and entropy-table leaves. The leaf layouts (SeqDef,
SeqStore_t, ZSTD_hufCTables_t, ZSTD_fseCTables_t, entropy metadata,
SeqCollector, ZSTD_Sequence) are pinned by compile-time asserts in
zstd_compress.c and by both-pointer-width layout tests in Rust.
ZSTD_buildSeqStore, block dispatch/splitting, and the block-size
estimation helpers remain C for a later slice.
The superblock module previously round-tripped through the C export of
ZSTD_buildBlockEntropyStats and mirrored the entropy leaf structs
privately. It now calls the crate-internal builder directly, and the
shared struct definitions moved to zstd_compress_stats; consequently
ZSTD_rust_compressSuperBlock() takes the two parameter scalars instead
of an opaque ZSTD_CCtx_params pointer, extracted by its C shim. Its
layout and repcode tests moved with the definitions.
One C helper family gets no shim: the static
ZSTD_entropyCompressSeqStore_wExtLitBuffer() had a single caller and
was folded into the Rust implementation.
Byte-identity was verified against the pre-change compressor: COPYING,
datagen -g5000000 -s7, and datagen -g300000 -s21 -P90, each at levels
1/3/9/19 and --fast=5, plus a superblock-heavy pass at level 19 with
--target-compressed-block-size=1024; all 18 frames are byte-identical,
covering the repeat-mode state machine, longOffsets, RLE/raw fallback,
and dstSize_tooSmall paths through the block splitter and superblock.
Test plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets -- -D
warnings && cargo test --all-targets (131 tests: new reference
vectors for seqToCodes, RLE table headers, empty-seqStore repeat
copies, literal-stats type selection, and repcode resolution in
copyBlockSequences)
- cargo build --release --no-default-features --features compression
and --features decompression
- make -C tests fuzzer && ./tests/fuzzer -i1 --no-big-tests (covers
ZSTD_generateSequences and ZDICT training over the Rust seqToCodes)
- make -C tests test-rust-lib-smoke
- ./tests/zstreamtest -i1 and ./tests/zstreamtest --newapi -t1 -i1
- ./tests/decodecorpus -t -T1s (decodecorpus links Rust seqToCodes)
- /tmp/ref vs /tmp/got frame diff as described above: byte-identical
Port lib/legacy/zstd_v01.c (the frozen zstd v0.1 decoder) to
rust/src/legacy/zstd_v01.rs as the first legacy-format port on the new
scaffolding, and reduce the C file to a declaration-only shim that
keeps its header includes for configuration and platform preprocessor
behavior.
Frozen-decoder policy: zstd_v01.c embeds its own v0.1-era FSE and
Huff0 snapshot, distinct from every other release. The Rust port is a
line-by-line translation with the same table layouts (FSE_DTable as a
u32 header word plus packed newState/symbol/nbBits entries, the Huff0
u16 DTable with byte/nbBits pairs), the same arithmetic including
wrap-around and pointer-comparison quirks (e.g. the offset-vs-base
address check in ZSTD_execSequence), the same internal FSE error space
(size_t)-1..-7, and the same public ZSTD error codes. It reuses no
modern Rust entropy module; its only crate dependency is `errors`,
matching the C file's error_private.h include. The 32-bit-only reload
points are kept as compile-time conditions on usize::BITS.
Symbol takeover boundary: all nine ZSTDv01_* entry points from
zstd_v01.h now come from Rust as context-free #[no_mangle] extern "C"
functions (isError, decompress, decompressDCtx,
findFrameSizeInfoLegacy, createDCtx, freeDCtx, resetDCtx,
nextSrcSizeToDecompress, decompressContinue). zstd_legacy.h only uses
the first four for v0.1; streaming for v0.1-v0.3 intentionally returns
version_unsupported there, unchanged. The ZSTDv01_Dctx struct
definition moves entirely into Rust: C code only ever holds an opaque
pointer (zstd_v01.h forward-declares the type), and the context is
malloc/free-allocated exactly like the C version so create/free may
pair across the language boundary.
Byte-identity verification against the pristine pre-migration C build
(f8745da6, pure C, ZSTD_LEGACY_SUPPORT=1):
- Real v0.1 frames were generated by building the v0.1.0 git tag and
compressing text, random, and 426 KB multi-block inputs. A one-shot
ZSTD_decompress harness linked once against the pristine C libzstd.a
and once against the Rust-backed libzstd.a produced bit-identical
outputs for all frames.
- A direct ZSTDv01_* probe (one-shot decode, dst-too-small, truncated
input, bad magic, findFrameSizeInfoLegacy, and the streaming
continue loop) printed identical results, including exact error
codes (-70 dstSize_tooSmall, -72 srcSize_wrong, -10 prefix_unknown)
and identical dBound values.
- zstd -l -v on v0.1 files matches the pristine binary; CLI streaming
decode of v0.1 fails with the same "Version not supported" in both,
by design of zstd_legacy.h.
Unit tests embed three v0.1.0-generated fixtures (entropy-coded,
raw-block, and four-block frames) plus the truncation, bad-magic,
small-destination, and streaming-API cases, all asserting the exact C
error codes above. Note that `make -C tests test-legacy` only covers
v0.4+ frames, so the embedded fixtures and the harness comparison are
the actual v0.1 coverage.
Test plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets
--features legacy-v01 -- -D warnings && cargo test --all-targets
--features legacy-v01 (127 tests, 9 for v0.1)
- cargo clippy/test --no-default-features --features
decompression,legacy-v01 (module builds standalone)
- make -C tests fuzzer && ./tests/fuzzer -i1 --no-big-tests, also with
ZSTD_LEGACY_SUPPORT=1 (mixed Rust v0.1 + C v0.2-0.7 link)
- make -C tests test-rust-lib-smoke && make -C tests test-legacy
- make -C programs zstd (default and ZSTD_LEGACY_SUPPORT=1); nm shows
the nine ZSTDv01_* symbols provided by Rust at level 1
- make -C lib libzstd.a ZSTD_LEGACY_SUPPORT=0 (no legacy symbols) and
meson -Dlegacy_level=1 shared library exporting all nine
The legacy decoders (lib/legacy/zstd_v01.c .. zstd_v07.c) are next in
the Rust migration. Each of those files is a frozen snapshot of the
FSE/Huff0 entropy coders and frame logic of one historical release, so
their ports must not reuse the modern Rust entropy modules and must not
share code with each other: outputs and error codes have to stay
byte-identical to the frozen C forever. This commit installs the
build-system scaffolding so seven per-version ports can land
independently, each adding only its own module file plus a one-line
registration in rust/src/legacy/mod.rs.
Cargo grows features legacy-v01 .. legacy-v07. They are never default
features: the C build defaults differ per build system, so each build
system passes the list explicitly, derived from its own legacy
configuration:
- lib/Makefile and programs/Makefile map ZSTD_LEGACY_SUPPORT=N to the
features for versions N..7 (0 disables legacy), mirroring the
ZSTD_LEGACY_FILES selection in lib/libzstd.mk.
- tests/Makefile always enables all seven features because its
ZSTDLEGACY_FILES wildcard compiles every lib/legacy/*.c regardless of
the dispatch level.
- build/meson maps legacy_level exactly like the makefiles; build/cmake
enables all seven whenever ZSTD_LEGACY_SUPPORT is ON because it
always compiles all seven C files (ZSTD_LEGACY_LEVEL only selects the
C dispatch).
Every build system also encodes the legacy selection in the Rust target
directory name (e.g. c1-d1-default-legacy5), for the same reason the
HUF mode is encoded there: a cached archive built for one configuration
must never be linked into a build expecting another. In tests/Makefile
the legacy level additionally flows into the existing HUF C-mode stamp,
so the flat C test objects (which bake -DZSTD_LEGACY_SUPPORT into the
dispatch) are rebuilt whenever the level changes. In programs/Makefile
the compress-only, decompress-only, and CLI archives keep
level-independent directories (RUST_HUF_MODE) because they are only
linked into ZSTD_LEGACY_SUPPORT=0 program variants and carry no legacy
features.
A feature whose version has not been ported yet gates nothing: the
module registration in rust/src/legacy/mod.rs is added by each port,
so enabling e.g. legacy-v05 today simply leaves that decoder in C.
This is what makes mixed C/Rust legacy levels link cleanly while the
seven ports land in any order.
Test plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets
-- -D warnings && cargo test --all-targets
- cargo clippy with --no-default-features --features
decompression,legacy-v01 and with all seven legacy features
- make -C tests fuzzer && ./tests/fuzzer -i1 --no-big-tests
- make -C tests test-rust-lib-smoke; make -C tests test-legacy
- make -C lib libzstd.a with ZSTD_LEGACY_SUPPORT=0, 1 and default (5)
- cmake configure and meson setup (including -Dlegacy_level=1) emit the
expected --features lists and legacy-suffixed target directories
Move the implementation of programs/benchfn.c into rust/src/benchfn.rs and
wire benchmark mode (-b/-e/-i) into the Rust CLI frontend, which previously
rejected those options as not yet implemented. `zstd -b1 -i0 FILE` and range
runs like `zstd -b5e6 -i0 FILE` work again, including the synthetic-sample
benchmark when no file is given.
benchfn.rs is a faithful port of the run/timing state machine:
BMK_benchFunction keeps the exact loop accounting (first-loop blockResults
and errorFn checks, dstSize summed on the first loop only, 0xE5 warm-up of
result buffers, nbLoops minimum of 1) and BMK_benchTimedFn keeps the same
convergence behavior (x10 workload growth for short runs, budget-based
nbLoops estimation, runs below half the run budget re-tried rather than
reported, best qualifying run returned). Arithmetic that C leaves to
unsigned wrap-around uses wrapping operations so debug builds cannot panic
where release C would wrap.
ABI notes: BMK_runTime_t and BMK_runOutcome_t are returned by value across
the C boundary and BMK_benchParams_t is passed by value, so all three are
repr(C) mirrors of benchfn.h; their field offsets are pinned by const
asserts in Rust and matching C static asserts in the benchfn.c shim, which
is now declaration-only. BMK_timedFnState_t stays opaque, fits the 64-byte
BMK_timedFnState_shell (compile-time checked), and is malloc/free-managed
so creation and destruction remain interchangeable with C callers.
The CLI parses -b (bench mode), -e (range end, digits attach directly,
defaulting to 0 like readU32FromChar) and -i (duration in seconds), then
dispatches through a new ZSTD_rust_cli_bench bridge in the zstdcli.c shim.
The bridge exists because benchmark availability is a C preprocessor
property (ZSTD_NOBENCH): orchestration and reporting stay in C benchzstd.c,
stripped variants (zstd-small, zstd-compress, zstd-decompress) compile the
stub branch and report "benchmark mode is not available in this build", and
the Rust side never references benchmark symbols directly. Level clamping
against ZSTD_maxCLevel() happens in the bridge, where the symbol is
guaranteed to exist whenever benchmarking is compiled in. -T selects the
worker count, defaulting to single-threaded like the C bench path; -S
(separate files) and --priority=rt remain unimplemented.
Makefile updates only extend the Rust source prerequisite lists with
benchfn.rs; the helpers-archive plumbing from the timefn commit already
links fullbench(-lib/-dll/32) and paramgrill, the benchfn consumers among
the C tests. Original C test sources are untouched.
Known pre-existing issues, unchanged by this commit: tests/fullbench-lib
fails to link at the base commit too (libzstd.a precedes fullbench.c in its
link line), and the cli-tests basic/help.sh, compression/levels.sh,
compression/golden.sh, and decompression/pass-through.sh scripts fail
identically with a base-commit binary because the Rust CLI frontend is
still a partial reimplementation.
Test Plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets -- -D warnings
&& cargo test --all-targets && cargo build --release
- cd rust/cli && cargo fmt --check && cargo clippy --all-targets -- -D
warnings && cargo test --all-targets; repeat tests with
--no-default-features plus features compression / decompression / (none)
- make -C programs zstd; ./programs/zstd -b1 -i0 lib/common/xxhash.c;
./programs/zstd -b5e6 -i0 programs/fileio.c; ./programs/zstd -b1 -i0
(synthetic); echo roundtrip via zstd | zstd -d
- make -C programs zstd-small zstd-compress zstd-decompress zstd-nolegacy
zstd-dictBuilder; zstd-small -b reports benchmark unavailable; compress/
decompress roundtrip across the split binaries
- make -C tests fullbench fuzzer zstreamtest paramgrill decodecorpus
poolTests fullbench32 fuzzer32; ./tests/fullbench -i0 (exercises Rust
BMK_benchTimedFn from C); ./tests/fullbench32 -i0; ./tests/fuzzer -i1
--no-big-tests; ./tests/poolTests; make -C tests test-rust-lib-smoke
- cli-tests subset: basic/version.sh, compression/basic.sh,
compression/multiple-files.sh pass; failing scripts match the base commit
Refs: rust/README.md
Move the implementation of programs/timefn.c into rust/src/timefn.rs. The
file provides the monotonic nanosecond clock (UTIL_getTime, span helpers,
UTIL_waitForNextTick, UTIL_support_MT_measurements) used by the CLI and by
several C test tools. timefn.c remains as a declaration-only shim so the
original source lists and header configuration keep working, and it pins the
ABI with static asserts: UTIL_time_t is returned by value and must stay a
plain 64-bit counter, which the Rust #[repr(C)] mirror also asserts.
Platform selection mirrors the C preprocessor structure: Windows uses
QueryPerformanceCounter, Apple targets use mach_absolute_time, and other
POSIX systems use libc clock_gettime(CLOCK_MONOTONIC). Only the unix path is
exercised by this environment; the Windows and Apple paths are written from
the C source and compile-checked logically but are untested here. The C90
clock() fallback is unreachable on Rust-supported targets, so multi-threaded
measurement support is always reported.
The symbols live in the program-only zstd-cli-rs package, keeping them out
of library builds. Linking that archive into C test binaries surfaced a
structural problem: rustc's local ThinLTO promotes internal symbols across
codegen units, so extracting the timefn object could drag in the zstd_cli
parser object, whose FIO_* externs test binaries cannot satisfy. The parser
is therefore gated behind a new additive `cli` cargo feature (default on).
Program archives build with cli,compression,decompression as before, while
tests/Makefile links a helpers-only archive (rust/target/cli-helpers) built
with --no-default-features, which contains no fileio references at all.
tests/Makefile gains build rules for the helpers archive and adds it as a
prerequisite of every binary that compiles the timefn shim: fullbench(32),
fullbench-lib, fullbench-dll, fuzzer(32), zstreamtest(32/asan/tsan/ubsan),
paramgrill, decodecorpus, and poolTests. Prerequisite order places the
archive after all C objects in `$^` link lines; the known-broken -dll
recipes filter to %.c, so they name the archive explicitly. Original C test
sources are untouched; only link inputs changed.
zstd-cli-rs now depends on libc (already used by the core crate) for
clock_gettime and the Mach timebase bindings.
Test Plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets -- -D warnings
&& cargo test --all-targets && cargo build --release
- cd rust/cli && cargo fmt --check && cargo clippy --all-targets -- -D
warnings && cargo test --all-targets; repeat tests with
--no-default-features plus features compression / decompression / (none)
- make -C programs zstd; roundtrip echo hello | zstd | zstd -d
- make -C tests fullbench fuzzer zstreamtest paramgrill decodecorpus
poolTests; ./tests/fullbench -i0; ./tests/fuzzer -i1 --no-big-tests;
./tests/poolTests; make -C tests test-rust-lib-smoke
- verified with nm that the helpers archive member defining UTIL_getTime has
no FIO_*/ZSTD_* undefined references
Refs: rust/README.md
Move the dictionary builder's suffix-array construction from
lib/dictBuilder/divsufsort.c to rust/src/divsufsort.rs, the first
dictBuilder module to migrate. It rides on the dict-builder cargo
feature dimension introduced by the previous commit.
divsufsort() is a self-contained algorithm (two-stage sort of type-B*
substrings via sssort, rank refinement via trsort, then induced sorting
of the full array), so its context-free signature allows a direct symbol
takeover: the Rust #[no_mangle] export provides the existing `divsufsort`
symbol and the C file becomes a declaration-only shim that just keeps the
header's prototypes in the build. Only divsufsort() moved; divbwt() has
no callers anywhere in zstd, so it is now declaration-only, keeping the
Rust export surface minimal. The unused openMP parameter is retained for
signature compatibility (zstd never defines LIBBSC_OPENMP).
The port is a mechanical translation of the exact configuration zstd
compiles: ALPHABET_SIZE=256, SS_INSERTIONSORT_THRESHOLD=8,
SS_BLOCKSIZE=1024, SS_MISORT_STACKSIZE=16, SS_SMERGE_STACKSIZE=32,
TR_STACKSIZE=64. Every C `int*` cursor into the SA buffer becomes an
`isize` index into a single `&mut [i32]` slice, preserving the pointer
arithmetic (including transient one-before-the-range cursors and the
bitwise-complement rank marking) while staying bounds-checked; all value
arithmetic keeps C int semantics. The C -1/-2 error results are
preserved, with Vec::try_reserve_exact standing in for the bucket-array
malloc failure path. Behavior is bit-identical by construction and by
measurement (see test plan); runtime on an 11 MB training buffer is
within ~5% of the C build end-to-end.
Users see no behavioral change: dictionaries trained through
ZDICT_trainFromBuffer_legacy() are byte-identical to the C build. The
only external difference is that the never-called `divbwt` symbol is no
longer defined in the library.
Test plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets
-- -D warnings && cargo test --all-targets && cargo build --release
(125 tests pass; new unit tests cover empty/one/two-byte inputs,
all-equal bytes, an exact hand-computed "abracadabra" SA, and
fixed-seed LCG buffers at 256-, 4-, and 2-symbol alphabets verified
against a naive reference sort plus permutation/sorted invariants)
- Feature matrix: cargo build --release --no-default-features
--features compression,decompression (and decompression-only,
compression-only, compression,dict-builder); `divsufsort` is exported
only when dict-builder is enabled
- make -C tests fuzzer && ./tests/fuzzer -i1 --no-big-tests (includes
ZDICT training tests): pass
- make -C tests test-rust-lib-smoke: pass
- make -C tests test-invalidDictionaries: pass
- make -C programs zstd zstd-dictBuilder zstd-small zstd-compress
zstd-decompress: build; compress/decompress round-trip verified
- Byte-identity vs pristine C build (commit 959e4852): a harness calling
ZDICT_trainFromBuffer_legacy() (the only zstd path reaching
divsufsort) and divsufsort() directly, linked against both libzstd.a
builds, produces byte-identical dictionaries (80,288 B and full
112,640 B capacity) and byte-identical suffix arrays on a 1 MB source
set and an 11 MB binary/repetitive set; a differential driver over 148
random and structured buffers (sizes 3..6000, alphabets 1..256,
Fibonacci word, sawtooth, 6 KB near-constant) shows zero mismatches.
The CLI --train path could not be exercised because the Rust CLI
frontend rejects --train in both the pristine and ported builds (a
pre-existing migration gap unrelated to this change).
The Rust CLI frontend rejected --single-thread, but tests/playTests.sh
uses it 28 times, so the flag is required before the original CLI test
suite can gate the migration.
Mirror the C zstdcli.c semantics: --single-thread pins zero workers and
sets a latch that suppresses the automatic core-count resolution, so
fileio receives nbWorkers == 0 and runs its single-thread streaming
mode (slightly different from -T1, which uses one worker thread). A
bare zero from -T0 or the zstdmt program name still auto-detects the
core count, and a later -T# overrides the pinned worker count while the
latch stays set, exactly as the C variable pair behaved.
Test plan:
- cd rust/cli && cargo clippy --all-targets -- -D warnings && cargo
test --all-targets (plus the compression-only and decompression-only
feature matrices); new parser tests cover the flag, the -T override
order, and rejection of an attached value.
- make -C programs zstd, then: --single-thread -3/-19 round-trips
against COPYING via cmp; --single-thread=1 fails with "does not take
an argument".
Move the context-free compression-parameter logic of zstd_compress.c to
rust/src/zstd_compress_params.rs: the compression-level tables (formerly
clevels.h), parameter bounds/checking/clamping, cycle log, level-table
selection, source/dictionary parameter adjustment, default frame
parameters, and the match-state/CDict size estimators.
The boundary follows the module's design notes: Rust owns only leaves
whose behavior is independent of C preprocessor configuration. C keeps
the public ZSTD_* symbols and feeds the leaves everything that is
configuration-owned as explicit scalars:
- The ZSTD_EXCLUDE_*_BLOCK_COMPRESSOR strategy cascade stays in
ZSTD_adjustCParams_internal() ahead of the Rust adjustment leaf, so
reduced builds keep their fallback policy.
- Workspace estimation receives struct sizes (ZSTD_CDict, ZSTD_match_t,
ZSTD_optimal_t), HUF workspace size, and the sanitizer redzone size,
because those depend on private layouts and ASAN configuration.
- ZSTD_cParam_getBounds() forwards only the compression level and the
seven core parameters; all other parameter bounds remain C.
- Frozen private constants the leaves hardcode (short-cache and row-hash
tag widths, MaxML/MaxLL/MaxOff/Litbits, ZSTD_OPT_SIZE, cwksp alignment)
are pinned by ZSTD_STATIC_ASSERTs at the C call sites.
Two latent 32-bit bugs in the previously unwired module were fixed
before integration: dictAndWindowLog's max window size and the
window-resize threshold were hardcoded to the 64-bit constants
(1<<31, 1<<30) instead of deriving from ZSTD_WINDOWLOG_MAX, which is
30 on 32-bit targets.
clevels.h is no longer included anywhere but stays in-tree as the
reference for mechanical comparison against the Rust table.
Test plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets -- -D
warnings && cargo test --all-targets (125 tests)
- make -C tests fuzzer && ./tests/fuzzer -i1 --no-big-tests
- make -C tests test-rust-lib-smoke
- Byte-identity: zstd CLI frames for COPYING, a 250 KB C source, and a
5 MB datagen sample at levels 1/3/9/19/--fast=5 are identical between
this change and its parent commit.
Continue the incremental zstd_compress.c migration with its frame
serialization leaves: ZSTD_writeFrameHeader(), the public
ZSTD_writeSkippableFrame() ABI, and ZSTD_writeLastEmptyBlock() now live
in rust/src/zstd_compress_frame.rs.
ZSTD_writeFrameHeader() reads five fields out of ZSTD_CCtx_params, whose
layout is private to zstd_compress.c and sensitive to build
configuration. Rather than mirror that structure in Rust, the C
function keeps its original static signature and forwards the scalar
fields to ZSTD_rust_writeFrameHeader(), so no parameter-structure layout
crosses the language boundary. The other two functions take only
pointer/size arguments and are exported directly, replacing their C
bodies outright.
Behavior differences are limited to hardening in release builds: the
Rust leaf clamps a window-size shift that C would leave undefined for a
malformed windowLog, and ZSTD_writeSkippableFrame() rejects a srcSize +
header overflow instead of comparing against a wrapped sum. Both paths
are unreachable through validated callers, so compressed output is
byte-identical.
Remaining zstd_compress.c work: parameter selection and validation,
context lifecycle, block dispatch, dictionary loading, and the streaming
state machine.
Test plan:
- cd rust && cargo fmt --check && cargo clippy --all-targets -- -D
warnings && cargo test --all-targets (118 tests, includes new frame
header/skippable/last-block reference vectors)
- make -C tests fuzzer && ./tests/fuzzer -i1 --no-big-tests
- make -C tests test-rust-lib-smoke
Move long-distance matching and high-level decompression from C shims into
Rust. The decoder now owns context, dictionary, parameter, one-shot, and
buffered streaming state while C retains allocation/configuration, legacy,
and trace leaves.
Move CLI parsing, safety policy, and dispatch into a separate Rust static
archive. Keeping it separate prevents library builds from retaining FIO
symbols, while C continues to own file opening, replacement, and I/O.
Program targets now select matching compression/decompression archives.
The remaining C boundary is intentional: high-level compression, optimal
parsing, dictionary building, legacy callbacks, and CLI file I/O still need
migration.
Test Plan:
- cargo test --all-targets (native and i686)
- cargo test --all-targets in rust/cli (native and i686)
- CLI crate compression-only and decompression-only feature tests
- native and i686 fuzzer/zstreamtest runs, plus legacy and dictionary tests
- ZSTD_C_PREDICT and ZSTD_HEAPMODE=0 fuzzer coverage
- library, dynamic-link, and program-target build/round-trip matrix
Refs: rust/README.md
Move the binary-tree table maintenance shared by optimal compression strategies
into Rust. A small C projection preserves the private match-state boundary;
the dynamic-programming parser and match selection remain C-owned for now.
The Rust implementation covers prefix and external-dictionary tree updates and
preserves the optional C predictor path. The component map now distinguishes
this migrated tree layer from the remaining optimal parser.
Test Plan:
- cargo test --all-targets
- cargo test --target i686-unknown-linux-gnu --all-targets
- cargo clippy && cargo clippy --benches && cargo clippy --tests
- cargo +nightly fmt
- make -B -C tests -j2 fuzzer zstreamtest invalidDictionaries
- ./tests/fuzzer -s5346 -i1 --no-big-tests
- ./tests/zstreamtest -i3000 -s334462
- ./tests/invalidDictionaries
- make -B -C tests fuzzer32 MOREFLAGS=-DZSTD_C_PREDICT
- ./tests/fuzzer32 -s5346 -i1 --no-big-tests
- byte-compare C and Rust-control CLI output at levels 13, 16, 19, and 22
for random, patterned, zero, and dictionary inputs with and without
ZSTD_C_PREDICT
Refs: rust/README.md
Move literal decoding, sequence-table construction, FSE sequence decoding, and
sequence execution into Rust. The C shim retains ownership of the configured
decoder context and passes only the leaf state needed by the block codec.
Correct the two high offset-code bases while porting the tables. Their prior
values made valid large-window streams decode as corrupted data; the new unit
test fixes the exact values and a native zstream regression exercises them.
High-level frame and streaming context control remains C for now.
Test Plan:
- cargo test --all-targets
- cargo test --target i686-unknown-linux-gnu --all-targets
- cargo clippy && cargo clippy --benches && cargo clippy --tests
- cargo +nightly fmt
- make -B -C tests -j2 fuzzer zstreamtest invalidDictionaries poolTests
- ./tests/fuzzer -s5346 -i1 --no-big-tests
- ./tests/zstreamtest -i3000 -s334462
- ./tests/invalidDictionaries
- timeout 20s stdbuf -oL ./tests/poolTests
Refs: rust/README.md
Move the two-table fast match finder into Rust while retaining a small C
projection of the private match-state. The Rust implementation handles normal,
attached-dictionary, and external-dictionary matching without exposing the
full C context ABI. The C entry points and build-time exclusion guards remain
unchanged for configured consumers.
Document the migrated matcher in the Rust component map and narrow the
remaining-C boundary accordingly.
Test Plan:
- cargo test --all-targets
- cargo test --target i686-unknown-linux-gnu --all-targets
- cargo clippy && cargo clippy --benches && cargo clippy --tests
- cargo +nightly fmt
- make -B -C tests -j2 fuzzer zstreamtest invalidDictionaries poolTests
- ./tests/fuzzer -s5346 -i1 --no-big-tests
- ./tests/zstreamtest -i3000 -s334462
- ./tests/invalidDictionaries
- timeout 20s stdbuf -oL ./tests/poolTests
Refs: rust/README.md
Move the context-free public ZSTD_compressBound ABI into Rust while leaving
the stateful compressor context in C. The Rust implementation preserves the
size-width-specific input limit, macro arithmetic, and srcSize_wrong error
contract used by C callers.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
- cargo test zstd_compress_api::tests -- --nocapture
- cargo test --target i686-unknown-linux-gnu zstd_compress_api::tests
- make -B -C lib -j2 libzstd.a
- fuzzer -s5346 -i1 --no-big-tests
Refs: public ZSTD_COMPRESSBOUND macro in lib/zstd.h
Move fast hash-table filling and no-dictionary, external-dictionary, and
attached-CDict match loops into Rust. The C shim keeps `ZSTD_MatchState_t`
opaque, extracts only its needed fields, and asserts the mirrored SeqStore
leaf layout so existing compression dispatch remains ABI-compatible.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
- cargo test zstd_fast::tests -- --nocapture
- cargo test --target i686-unknown-linux-gnu zstd_fast::tests -- --nocapture
- byte-identical C-control frames for dictionary and streaming variants
- fuzzer -s2066 -i5 --no-big-tests
- invalidDictionaries and zstreamtest -i1
Refs: Rust superblock port fde1d70c
Move subblock partitioning, literal and sequence section emission, entropy
fallback, and repcode repair into Rust. Keep a narrow C wrapper to read the
opaque compression context and invoke the existing C entropy-stat builder;
the Rust side owns only verified C-shaped leaf layouts.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
- cargo test zstd_compress_superblock::tests -- --nocapture
- cargo test --target i686-unknown-linux-gnu zstd_compress_superblock::tests
- byte-exact C control across 16 target-size and input-shape cases
- fuzzer, zstreamtest, invalidDictionaries, and bounded native test matrix
Refs: Rust sequence entropy port 887af204
Move FSE table-costing, table construction, encoding selection, and sequence
bitstream emission into Rust while retaining the existing C internal-header
boundary. The shim preserves all five C ABI entry points, so the surrounding
compressor continues to consume C-shaped sequence and entropy-table storage.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
- cargo test --all-targets
- cargo test --target i686-unknown-linux-gnu zstd_compress_sequences::tests
- C-vs-Rust differential across 163 payload cases on x86_64 and i686
- fuzzer, zstreamtest, and invalidDictionaries
Refs: Rust FSE compression port 5f9d607d
Link poolTests against the multithreaded object set and Rust static archive,
so its C callbacks exercise the migrated pool rather than compiling a private
C implementation. Preserve ZSTD_MULTITHREAD for the test translation unit;
without it, its pthread test helpers become no-ops while the Rust pool runs
concurrently. Add a Rust regression for draining a small queue after reducing
the worker limit.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
- cargo test shrinking_the_limit_keeps_draining_a_small_queue -- --nocapture
- make -B -C tests poolTests && timeout 20s stdbuf -oL ./tests/poolTests
Refs: Rust pool migration 26b5e202
Move raw, RLE, and Huffman literal-section encoding into the Rust
compatibility archive. The surrounding C block compressor continues to pass
its existing entropy workspace and Huffman-table state through the unchanged
internal ABI.
The port preserves literal header choices, compression-gain decisions,
repeat-table transitions, and 1X/4X encoder selection. It lets ordinary C
compression paths exercise Rust code without widening this commit into the
remaining frame compressor.
Test Plan:
- cargo clippy, cargo clippy --benches, cargo clippy --tests, and nightly fmt
- cargo test --all-targets (94 passed) and feature-only cargo checks
- native fuzzer, zstreamtest, invalidDictionaries, and CLI round trip
- compare literals and next-table bytes with pristine C on x86_64 and i686
Refs: rust/README.md compression-primitives map
Move Huffman table construction, table serialization, and one- and
four-stream payload encoding from huf_compress.c into the Rust compatibility
archive. The declaration-only C shim preserves the existing internal ABI,
so the remaining C compressor can call the migrated implementation unchanged.
The translation keeps CTable layouts, workspace checks, repeat-table
selection, and bitstream output compatible with the original encoder. This
lets native C consumers exercise the Rust implementation through libzstd.
Test Plan:
- cargo clippy, cargo clippy --benches, and cargo clippy --tests
- cargo +nightly fmt and cargo test --all-targets (88 passed)
- cargo check --no-default-features --features compression
- rebuild and run tests fuzzer, zstreamtest, and invalidDictionaries
- compare tables, headers, and 1X/4X streams with a renamed pristine C build
Refs: rust/README.md component map
Build feature-matched Rust archives for the native Make library path. Flatten
their members into libzstd.a so static consumers resolve C-to-Rust and
Rust-to-C references in one archive, and whole-archive link shared outputs so
every migrated public ABI export remains available.
Rust compression and decompression features now mirror the C partial-library
switches. This prevents compression-only artifacts from retaining DDict
references to decompression-only C helpers.
Add a C archive smoke test that round-trips data and exercises the DDict
lifecycle through lib/libzstd.a, rather than direct test-object links.
Test Plan:
- cargo fmt, strict Clippy, cargo test --all-targets, release build
- Rust checks with compression-only, decompression-only, and no features
- full, partial, forced-HUF, and 32-bit static/shared Make library probes
- test-rust-lib-smoke, fuzzer, zstreamtest, and invalidDictionaries
Refs: rust/README.md
ddidderr