feat(compress): move frame parameter updates into Rust

Move ZSTD_CCtx_setFParams's ordered frame-flag updates into the Rust
projection. C retains the context-bound ZSTD_CCtx_setParameter callback while
Rust preserves content-size, checksum, and dictionary-ID boolean conversions,
update order, and first-error propagation.

Test Plan:
- ulimit -v 41943040; CARGO_BUILD_JOBS=1 cargo test --manifest-path rust/Cargo.toml set_fparams -- --test-threads=1
- ulimit -v 41943040; CARGO_BUILD_JOBS=1 cargo clippy --manifest-path rust/Cargo.toml --all-targets -- -D warnings
- ulimit -v 41943040; make -B -C programs -j1 zstd
- git diff --cached --check

lib/compress/zstd_compress.c

@@ -213,6 +213,19 @@ typedef char ZSTD_rust_set_cparams_state_layout[
          && offsetof(ZSTD_rust_setCParamsState, setParameter) == 2 * sizeof(void*)
          && sizeof(ZSTD_rust_setCParamsState) == 3 * sizeof(void*))
         ? 1 : -1];
+typedef size_t (*ZSTD_rust_setFParamsSetParameter_f)(
+        void* context, int param, int value);
+typedef struct {
+    void* callbackContext;
+    ZSTD_rust_setFParamsSetParameter_f setParameter;
+} ZSTD_rust_setFParamsState;
+size_t ZSTD_rust_setFParams(const ZSTD_rust_setFParamsState* state,
+                            ZSTD_frameParameters fParams);
+typedef char ZSTD_rust_set_fparams_state_layout[
+        (offsetof(ZSTD_rust_setFParamsState, callbackContext) == 0
+         && offsetof(ZSTD_rust_setFParamsState, setParameter) == sizeof(void*)
+         && sizeof(ZSTD_rust_setFParamsState) == 2 * sizeof(void*))
+        ? 1 : -1];
 ZSTD_frameProgression ZSTD_rust_frameProgression(U64 consumedSrcSize,
                                                   size_t buffered,
                                                   U64 producedCSize);
@@ -1903,6 +1916,12 @@ static size_t ZSTD_rust_setCParams_setParameter(
     return ZSTD_CCtx_setParameter((ZSTD_CCtx*)context, (ZSTD_cParameter)param, value);
 }
 
+static size_t ZSTD_rust_setFParams_setParameter(
+        void* context, int param, int value)
+{
+    return ZSTD_CCtx_setParameter((ZSTD_CCtx*)context, (ZSTD_cParameter)param, value);
+}
+
 size_t ZSTD_CCtx_setCParams(ZSTD_CCtx* cctx, ZSTD_compressionParameters cparams)
 {
     ZSTD_rust_setCParamsState state;
@@ -1916,12 +1935,12 @@ size_t ZSTD_CCtx_setCParams(ZSTD_CCtx* cctx, ZSTD_compressionParameters cparams)
 
 size_t ZSTD_CCtx_setFParams(ZSTD_CCtx* cctx, ZSTD_frameParameters fparams)
 {
+    ZSTD_rust_setFParamsState state;
     ZSTD_STATIC_ASSERT(sizeof(fparams) == 3 * 4 /* all params are listed below */);
     DEBUGLOG(4, "ZSTD_CCtx_setFParams");
-    FORWARD_IF_ERROR(ZSTD_CCtx_setParameter(cctx, ZSTD_c_contentSizeFlag, fparams.contentSizeFlag != 0), "");
+    state.callbackContext = cctx;
-    FORWARD_IF_ERROR(ZSTD_CCtx_setParameter(cctx, ZSTD_c_checksumFlag, fparams.checksumFlag != 0), "");
+    state.setParameter = ZSTD_rust_setFParams_setParameter;
-    FORWARD_IF_ERROR(ZSTD_CCtx_setParameter(cctx, ZSTD_c_dictIDFlag, fparams.noDictIDFlag == 0), "");
+    return ZSTD_rust_setFParams(&state, fparams);
-    return 0;
 }
 
 size_t ZSTD_CCtx_setParams(ZSTD_CCtx* cctx, ZSTD_parameters params)

rust/src/zstd_compress.rs

@@ -23,9 +23,9 @@ use crate::zstd_compress_frame::{
 };
 use crate::zstd_compress_literals::min_gain;
 use crate::zstd_compress_params::{
-    ZSTD_compressionParameters, ZSTD_parameters, ZSTD_rust_params_adjustCParams,
+    ZSTD_compressionParameters, ZSTD_frameParameters, ZSTD_parameters,
-    ZSTD_rust_params_maxNbSeq, ZSTD_rust_params_selectCParams, ZSTD_RUST_CPM_NO_ATTACH_DICT,
+    ZSTD_rust_params_adjustCParams, ZSTD_rust_params_maxNbSeq, ZSTD_rust_params_selectCParams,
-    ZSTD_RUST_PS_AUTO, ZSTD_RUST_PS_DISABLE,
+    ZSTD_RUST_CPM_NO_ATTACH_DICT, ZSTD_RUST_PS_AUTO, ZSTD_RUST_PS_DISABLE,
 };
 use crate::zstd_compress_sequences::SeqDef;
 use crate::zstd_compress_stats::{
@@ -120,6 +120,9 @@ const ZSTD_C_SEARCH_LOG: c_int = 104;
 const ZSTD_C_MIN_MATCH: c_int = 105;
 const ZSTD_C_TARGET_LENGTH: c_int = 106;
 const ZSTD_C_STRATEGY: c_int = 107;
+const ZSTD_C_CONTENT_SIZE_FLAG: c_int = 200;
+const ZSTD_C_CHECKSUM_FLAG: c_int = 201;
+const ZSTD_C_DICT_ID_FLAG: c_int = 202;
 const ZSTD_CSTREAM_STAGE_LOAD: c_int = 1;
 const ZSTD_CSTREAM_STAGE_FLUSH: c_int = 2;
 const ZSTD_BSS_COMPRESS: c_int = 0;
@@ -1267,6 +1270,47 @@ pub unsafe extern "C" fn ZSTD_rust_setCParams(
     0
 }
 
+type SetFParamsSetParameterFn = unsafe extern "C" fn(*mut c_void, c_int, c_int) -> usize;
+
+/// Explicit projection for `ZSTD_CCtx_setFParams`.
+#[repr(C)]
+pub struct ZSTD_rust_setFParamsState {
+    callback_context: *mut c_void,
+    set_parameter: SetFParamsSetParameterFn,
+}
+
+const _: () = {
+    assert!(offset_of!(ZSTD_rust_setFParamsState, callback_context) == 0);
+    assert!(offset_of!(ZSTD_rust_setFParamsState, set_parameter) == size_of::<usize>());
+    assert!(size_of::<ZSTD_rust_setFParamsState>() == 2 * size_of::<usize>());
+};
+
+#[no_mangle]
+pub unsafe extern "C" fn ZSTD_rust_setFParams(
+    state: *const ZSTD_rust_setFParamsState,
+    fparams: ZSTD_frameParameters,
+) -> usize {
+    if state.is_null() {
+        return ERROR(ZstdErrorCode::Generic);
+    }
+    let state = unsafe { &*state };
+    let parameters = [
+        (
+            ZSTD_C_CONTENT_SIZE_FLAG,
+            (fparams.contentSizeFlag != 0) as c_int,
+        ),
+        (ZSTD_C_CHECKSUM_FLAG, (fparams.checksumFlag != 0) as c_int),
+        (ZSTD_C_DICT_ID_FLAG, (fparams.noDictIDFlag == 0) as c_int),
+    ];
+    for (param, value) in parameters {
+        let result = unsafe { (state.set_parameter)(state.callback_context, param, value) };
+        if ERR_isError(result) {
+            return result;
+        }
+    }
+    0
+}
+
 type CompressStreamBlockFn =
     unsafe extern "C" fn(*mut c_void, *mut c_void, usize, *const c_void, usize) -> usize;
 type CompressStreamResetFn = unsafe extern "C" fn(*mut c_void) -> usize;
@@ -5575,7 +5619,6 @@ pub unsafe extern "C" fn ZSTD_compressStream2(
 mod tests {
     use super::*;
     use crate::errors::ERR_getErrorCode;
-    use crate::zstd_compress_params::ZSTD_frameParameters;
     use std::io::Write;
     use std::process::{Command, Stdio};
 
@@ -9802,6 +9845,104 @@ mod tests {
         assert_eq!(context.parameter_calls.len(), 4);
     }
 
+    #[derive(Default)]
+    struct SetFParamsTestContext {
+        parameter_calls: Vec<(c_int, c_int)>,
+        set_result: usize,
+        fail_at: usize,
+    }
+
+    unsafe fn set_fparams_test_context(context: *mut c_void) -> &'static mut SetFParamsTestContext {
+        unsafe { &mut *context.cast::<SetFParamsTestContext>() }
+    }
+
+    unsafe extern "C" fn set_fparams_test_set_parameter(
+        context: *mut c_void,
+        param: c_int,
+        value: c_int,
+    ) -> usize {
+        let context = unsafe { set_fparams_test_context(context) };
+        context.parameter_calls.push((param, value));
+        if context.fail_at != 0 && context.parameter_calls.len() == context.fail_at {
+            context.set_result
+        } else {
+            0
+        }
+    }
+
+    fn set_fparams_test_state(context: &mut SetFParamsTestContext) -> ZSTD_rust_setFParamsState {
+        ZSTD_rust_setFParamsState {
+            callback_context: (context as *mut SetFParamsTestContext).cast(),
+            set_parameter: set_fparams_test_set_parameter,
+        }
+    }
+
+    #[test]
+    fn set_fparams_preserves_parameter_order_and_boolean_conversions() {
+        let fparams = ZSTD_frameParameters {
+            contentSizeFlag: 0,
+            checksumFlag: 2,
+            noDictIDFlag: 7,
+        };
+        let mut context = SetFParamsTestContext::default();
+        let state = set_fparams_test_state(&mut context);
+
+        let result = unsafe { ZSTD_rust_setFParams(&state, fparams) };
+
+        assert_eq!(result, 0);
+        assert_eq!(
+            context.parameter_calls,
+            [
+                (ZSTD_C_CONTENT_SIZE_FLAG, 0),
+                (ZSTD_C_CHECKSUM_FLAG, 1),
+                (ZSTD_C_DICT_ID_FLAG, 0),
+            ]
+        );
+    }
+
+    #[test]
+    fn set_fparams_stops_after_the_first_parameter_error() {
+        let fparams = ZSTD_frameParameters {
+            contentSizeFlag: 1,
+            checksumFlag: 1,
+            noDictIDFlag: 0,
+        };
+        let mut context = SetFParamsTestContext {
+            set_result: ERROR(ZstdErrorCode::StageWrong),
+            fail_at: 1,
+            ..SetFParamsTestContext::default()
+        };
+        let state = set_fparams_test_state(&mut context);
+
+        let result = unsafe { ZSTD_rust_setFParams(&state, fparams) };
+
+        assert_eq!(result, ERROR(ZstdErrorCode::StageWrong));
+        assert_eq!(context.parameter_calls, [(ZSTD_C_CONTENT_SIZE_FLAG, 1)]);
+    }
+
+    #[test]
+    fn set_fparams_propagates_a_later_parameter_error_without_following_updates() {
+        let fparams = ZSTD_frameParameters {
+            contentSizeFlag: 1,
+            checksumFlag: 0,
+            noDictIDFlag: 0,
+        };
+        let mut context = SetFParamsTestContext {
+            set_result: ERROR(ZstdErrorCode::ParameterOutOfBound),
+            fail_at: 2,
+            ..SetFParamsTestContext::default()
+        };
+        let state = set_fparams_test_state(&mut context);
+
+        let result = unsafe { ZSTD_rust_setFParams(&state, fparams) };
+
+        assert_eq!(result, ERROR(ZstdErrorCode::ParameterOutOfBound));
+        assert_eq!(
+            context.parameter_calls,
+            [(ZSTD_C_CONTENT_SIZE_FLAG, 1), (ZSTD_C_CHECKSUM_FLAG, 0),]
+        );
+    }
+
     #[test]
     fn pledged_src_size_writes_the_init_stage_value_plus_one() {
         let mut pledged_src_size_plus_one = 0;