refactor(compress): move advanced one-shot order to Rust

ZSTD_compress_advanced_internal() still encoded the one-shot begin-then-end
sequence in C after public advanced parameter validation had moved behind Rust.
That left the public compression boundary split between Rust policy and a C
orchestration body, and made the begin-error ordering implicit in the C path.

Add an explicit C-layout state with opaque begin and end callbacks. Rust now
owns the ordering, forwards the source size as the pledged size, propagates a
begin error before invoking the end callback, and returns the end result. The
callbacks retain the private ZSTD_CCtx and ZSTD_CCtx_params layouts, so the
change moves policy and sequencing without exposing window, workspace,
matchfinder, or context internals to Rust. The existing advanced and
using-dictionary wrappers continue to use the same C private operations.

Test Plan:
- `git diff --cached --check` -- passed.
- `rustfmt --check --edition 2021 rust/src/zstd_compress.rs` -- passed.
- Not run: Cargo, make, native tests, builds, or heavy verification per request.
This commit is contained in:
2026-07-21 09:13:50 +02:00
parent cb770812fd
commit 19c3414095
2 changed files with 264 additions and 4 deletions
+58 -4
View File
@@ -678,6 +678,32 @@ typedef char ZSTD_rust_compress_advanced_state_layout[
== 2 * sizeof(void*)
&& sizeof(ZSTD_rust_compressAdvancedState) == 3 * sizeof(void*))
? 1 : -1];
typedef size_t (*ZSTD_rust_compressAdvancedInternalBegin_f)(
void* context, const void* dict, size_t dictSize,
const void* params, U64 pledgedSrcSize);
typedef size_t (*ZSTD_rust_compressAdvancedInternalEnd_f)(
void* context, void* dst, size_t dstCapacity,
const void* src, size_t srcSize);
typedef struct {
void* callbackContext;
ZSTD_rust_compressAdvancedInternalBegin_f begin;
ZSTD_rust_compressAdvancedInternalEnd_f end;
} ZSTD_rust_compressAdvancedInternalState;
size_t ZSTD_rust_compressAdvancedInternal(
const ZSTD_rust_compressAdvancedInternalState* state,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const void* dict, size_t dictSize,
const void* params);
typedef char ZSTD_rust_compress_advanced_internal_state_layout[
(offsetof(ZSTD_rust_compressAdvancedInternalState, callbackContext) == 0
&& offsetof(ZSTD_rust_compressAdvancedInternalState, begin)
== sizeof(void*)
&& offsetof(ZSTD_rust_compressAdvancedInternalState, end)
== 2 * sizeof(void*)
&& sizeof(ZSTD_rust_compressAdvancedInternalState)
== 3 * sizeof(void*))
? 1 : -1];
typedef void (*ZSTD_rust_compressUsingDictInitParams_f)(
void* context, const ZSTD_parameters* params, int compressionLevel);
typedef struct {
@@ -6950,6 +6976,12 @@ static size_t ZSTD_rust_compressAdvanced_compressInternal(
void* context, void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const void* dict, size_t dictSize);
static size_t ZSTD_rust_compressAdvancedInternal_begin(
void* context, const void* dict, size_t dictSize,
const void* params, U64 pledgedSrcSize);
static size_t ZSTD_rust_compressAdvancedInternal_end(
void* context, void* dst, size_t dstCapacity,
const void* src, size_t srcSize);
size_t ZSTD_compress_advanced (ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
@@ -6974,11 +7006,33 @@ size_t ZSTD_compress_advanced_internal(
const void* dict,size_t dictSize,
const ZSTD_CCtx_params* params)
{
ZSTD_rust_compressAdvancedInternalState state;
DEBUGLOG(4, "ZSTD_compress_advanced_internal (srcSize:%u)", (unsigned)srcSize);
FORWARD_IF_ERROR( ZSTD_compressBegin_internal(cctx,
dict, dictSize, ZSTD_dct_auto, ZSTD_dtlm_fast, NULL,
params, srcSize, ZSTDb_not_buffered) , "");
return ZSTD_compressEnd_public(cctx, dst, dstCapacity, src, srcSize);
state.callbackContext = cctx;
state.begin = ZSTD_rust_compressAdvancedInternal_begin;
state.end = ZSTD_rust_compressAdvancedInternal_end;
return ZSTD_rust_compressAdvancedInternal(
&state, dst, dstCapacity, src, srcSize,
dict, dictSize, params);
}
static size_t ZSTD_rust_compressAdvancedInternal_begin(
void* context, const void* dict, size_t dictSize,
const void* params, U64 pledgedSrcSize)
{
return ZSTD_compressBegin_internal(
(ZSTD_CCtx*)context, dict, dictSize,
ZSTD_dct_auto, ZSTD_dtlm_fast, NULL,
(const ZSTD_CCtx_params*)params,
pledgedSrcSize, ZSTDb_not_buffered);
}
static size_t ZSTD_rust_compressAdvancedInternal_end(
void* context, void* dst, size_t dstCapacity,
const void* src, size_t srcSize)
{
return ZSTD_compressEnd_public(
(ZSTD_CCtx*)context, dst, dstCapacity, src, srcSize);
}
static void ZSTD_rust_compressAdvanced_initParams(
+206
View File
@@ -3424,6 +3424,69 @@ pub unsafe extern "C" fn ZSTD_rust_compressAdvanced(
}
}
type CompressAdvancedInternalBeginFn =
unsafe extern "C" fn(*mut c_void, *const c_void, usize, *const c_void, u64) -> usize;
type CompressAdvancedInternalEndFn =
unsafe extern "C" fn(*mut c_void, *mut c_void, usize, *const c_void, usize) -> usize;
/// Explicit projection for the private-operation boundary behind the public
/// advanced compression wrappers.
///
/// Rust owns the begin-then-end ordering and stops before the end callback if
/// the private C begin operation fails. The C callbacks retain the
/// configuration-dependent `ZSTD_CCtx` and `ZSTD_CCtx_params` layouts.
#[repr(C)]
pub struct ZSTD_rust_compressAdvancedInternalState {
callback_context: *mut c_void,
begin: CompressAdvancedInternalBeginFn,
end: CompressAdvancedInternalEndFn,
}
const _: () = {
assert!(size_of::<CompressAdvancedInternalBeginFn>() == size_of::<usize>());
assert!(size_of::<CompressAdvancedInternalEndFn>() == size_of::<usize>());
assert!(offset_of!(ZSTD_rust_compressAdvancedInternalState, callback_context) == 0);
assert!(offset_of!(ZSTD_rust_compressAdvancedInternalState, begin) == size_of::<usize>());
assert!(offset_of!(ZSTD_rust_compressAdvancedInternalState, end) == 2 * size_of::<usize>());
assert!(size_of::<ZSTD_rust_compressAdvancedInternalState>() == size_of::<[usize; 3]>());
};
/// Run the one-shot advanced compression order while keeping private C state
/// behind the begin and end callbacks.
#[no_mangle]
pub unsafe extern "C" fn ZSTD_rust_compressAdvancedInternal(
state: *const ZSTD_rust_compressAdvancedInternalState,
dst: *mut c_void,
dst_capacity: usize,
src: *const c_void,
src_size: usize,
dict: *const c_void,
dict_size: usize,
params: *const c_void,
) -> usize {
if state.is_null() || params.is_null() {
return ERROR(ZstdErrorCode::Generic);
}
let state = unsafe { &*state };
if state.callback_context.is_null() {
return ERROR(ZstdErrorCode::Generic);
}
let begin_result = unsafe {
(state.begin)(
state.callback_context,
dict,
dict_size,
params,
src_size as u64,
)
};
if ERR_isError(begin_result) {
return begin_result;
}
unsafe { (state.end)(state.callback_context, dst, dst_capacity, src, src_size) }
}
type CompressBeginAdvancedInitParamsFn = unsafe extern "C" fn(*mut c_void, *const ZSTD_parameters);
type CompressBeginAdvancedBeginFn =
unsafe extern "C" fn(*mut c_void, *const c_void, usize, *const c_void, u64) -> usize;
@@ -18024,6 +18087,149 @@ mod tests {
assert!(context.events.is_empty());
}
#[derive(Default)]
struct CompressAdvancedInternalTestContext {
events: Vec<&'static str>,
begin_result: usize,
end_result: usize,
begin_dict: *const c_void,
begin_dict_size: usize,
begin_params: *const c_void,
pledged_src_size: u64,
end_dst: *mut c_void,
end_dst_capacity: usize,
end_src: *const c_void,
end_src_size: usize,
}
unsafe extern "C" fn compress_advanced_internal_test_begin(
context: *mut c_void,
dict: *const c_void,
dict_size: usize,
params: *const c_void,
pledged_src_size: u64,
) -> usize {
let context = unsafe { &mut *context.cast::<CompressAdvancedInternalTestContext>() };
context.events.push("begin");
context.begin_dict = dict;
context.begin_dict_size = dict_size;
context.begin_params = params;
context.pledged_src_size = pledged_src_size;
context.begin_result
}
unsafe extern "C" fn compress_advanced_internal_test_end(
context: *mut c_void,
dst: *mut c_void,
dst_capacity: usize,
src: *const c_void,
src_size: usize,
) -> usize {
let context = unsafe { &mut *context.cast::<CompressAdvancedInternalTestContext>() };
context.events.push("end");
context.end_dst = dst;
context.end_dst_capacity = dst_capacity;
context.end_src = src;
context.end_src_size = src_size;
context.end_result
}
fn compress_advanced_internal_test_state(
context: &mut CompressAdvancedInternalTestContext,
) -> ZSTD_rust_compressAdvancedInternalState {
ZSTD_rust_compressAdvancedInternalState {
callback_context: (context as *mut CompressAdvancedInternalTestContext).cast(),
begin: compress_advanced_internal_test_begin,
end: compress_advanced_internal_test_end,
}
}
#[test]
fn compress_advanced_internal_preserves_begin_then_end_order() {
let mut context = CompressAdvancedInternalTestContext {
end_result: 31,
..CompressAdvancedInternalTestContext::default()
};
let state = compress_advanced_internal_test_state(&mut context);
let mut dst = [0u8; 8];
let src = [1u8, 2, 3];
let dict = [4u8, 5];
let params = [6u8; 4];
let result = unsafe {
ZSTD_rust_compressAdvancedInternal(
&state,
dst.as_mut_ptr().cast(),
dst.len(),
src.as_ptr().cast(),
src.len(),
dict.as_ptr().cast(),
dict.len(),
params.as_ptr().cast(),
)
};
assert_eq!(result, context.end_result);
assert_eq!(context.events, ["begin", "end"]);
assert_eq!(context.begin_dict, dict.as_ptr().cast());
assert_eq!(context.begin_dict_size, dict.len());
assert_eq!(context.begin_params, params.as_ptr().cast());
assert_eq!(context.pledged_src_size, src.len() as u64);
assert_eq!(context.end_dst, dst.as_mut_ptr().cast());
assert_eq!(context.end_dst_capacity, dst.len());
assert_eq!(context.end_src, src.as_ptr().cast());
assert_eq!(context.end_src_size, src.len());
}
#[test]
fn compress_advanced_internal_stops_before_end_after_begin_error() {
let mut context = CompressAdvancedInternalTestContext {
begin_result: ERROR(ZstdErrorCode::StageWrong),
end_result: 37,
..CompressAdvancedInternalTestContext::default()
};
let state = compress_advanced_internal_test_state(&mut context);
let params = [0u8; 1];
let result = unsafe {
ZSTD_rust_compressAdvancedInternal(
&state,
ptr::null_mut(),
0,
ptr::null(),
17,
ptr::null(),
0,
params.as_ptr().cast(),
)
};
assert_eq!(result, ERROR(ZstdErrorCode::StageWrong));
assert_eq!(context.events, ["begin"]);
}
#[test]
fn compress_advanced_internal_rejects_missing_params_before_callbacks() {
let mut context = CompressAdvancedInternalTestContext::default();
let state = compress_advanced_internal_test_state(&mut context);
let result = unsafe {
ZSTD_rust_compressAdvancedInternal(
&state,
ptr::null_mut(),
0,
ptr::null(),
0,
ptr::null(),
0,
ptr::null(),
)
};
assert_eq!(result, ERROR(ZstdErrorCode::Generic));
assert!(context.events.is_empty());
}
#[derive(Default)]
struct CompressBeginAdvancedTestContext {
events: Vec<&'static str>,