ffi: remove c_set_rawElementsTransaction

Author: apoelstra

simplicity-sys/depend/env.c

@@ -25,23 +25,6 @@ const size_t rustsimplicity_0_5_c_alignof_rawElementsTransaction = alignof(rawEl
 const size_t rustsimplicity_0_5_c_alignof_rawElementsTapEnv = alignof(rawElementsTapEnv);
 const size_t rustsimplicity_0_5_c_alignof_txEnv = alignof(txEnv);
 
-void rustsimplicity_0_5_c_set_rawElementsTransaction(rawElementsTransaction *result, unsigned int version,
-                          const unsigned char *txid,
-                          const rawElementsInput *input, unsigned int numInputs,
-                          const rawElementsOutput *output, unsigned int numOutputs,
-                          unsigned int lockTime)
-{
-    *result = (rawElementsTransaction){
-        .version = version,
-        .txid = txid,
-        .input = input,
-        .numInputs = numInputs,
-        .output = output,
-        .numOutputs = numOutputs,
-        .lockTime = lockTime,
-    };
-}
-
 void rustsimplicity_0_5_c_set_rawElementsTapEnv(rawElementsTapEnv *result, const unsigned char *controlBlock, unsigned char pathLen, const unsigned char *scriptCMR)
 {
     *result = (rawElementsTapEnv){.controlBlock = controlBlock, .pathLen = pathLen, .scriptCMR = scriptCMR};

simplicity-sys/src/c_jets/c_env/elements.rs

@@ -113,13 +113,13 @@ pub struct CRawInput<'raw> {
 #[derive(Debug)]
 #[repr(C)]
 pub struct CRawTransaction<'raw> {
-    txid: *const c_uchar,
-    inputs: *const CRawInput<'raw>,
-    outputs: *const CRawOutput<'raw>,
-    version: u32,
-    locktime: u32,
-    n_inputs: u32,
-    n_outputs: u32,
+    pub txid: &'raw [c_uchar; 32],
+    pub inputs: *const CRawInput<'raw>,
+    pub outputs: *const CRawOutput<'raw>,
+    pub n_inputs: u32,
+    pub n_outputs: u32,
+    pub version: u32,
+    pub locktime: u32,
 }
 
 #[derive(Debug)]
@@ -173,17 +173,6 @@ extern "C" {
     #[link_name = "rustsimplicity_0_5_c_alignof_txEnv"]
     pub static c_alignof_txEnv: c_size_t;
 
-    #[link_name = "rustsimplicity_0_5_c_set_rawElementsTransaction"]
-    pub fn c_set_rawTransaction(
-        result: *mut CRawTransaction,
-        version: c_uint,
-        txid: *const c_uchar,
-        input: *const CRawInput,
-        numInputs: c_uint,
-        output: *const CRawOutput,
-        numOutputs: c_uint,
-        lockTime: c_uint,
-    );
     #[link_name = "rustsimplicity_0_5_c_set_rawElementsTapEnv"]
     pub fn c_set_rawTapEnv(
         result: *mut CRawTapEnv,

src/jet/elements/c_env.rs

@@ -4,7 +4,7 @@
 //!
 
 use hashes::Hash;
-use std::os::raw::{c_uchar, c_uint};
+use std::os::raw::c_uchar;
 
 use elements::{
     confidential,
@@ -128,20 +128,19 @@ pub(super) fn new_tx(
     for (out, out_data) in tx.output.iter().zip(tx_data.outputs.iter()) {
         raw_outputs.push(new_raw_output(out, out_data));
     }
+
+    let c_raw_tx = c_elements::CRawTransaction {
+        txid: txid.as_raw_hash().as_byte_array(),
+        inputs: raw_inputs.as_ptr(),
+        outputs: raw_outputs.as_ptr(),
+        n_inputs: raw_inputs.len().try_into().expect("sane length"),
+        n_outputs: raw_outputs.len().try_into().expect("sane length"),
+        version: tx.version,
+        locktime: tx.lock_time.to_consensus_u32(),
+    };
     unsafe {
-        let mut raw_tx = std::mem::MaybeUninit::<c_elements::CRawTransaction>::uninit();
-        c_elements::c_set_rawTransaction(
-            raw_tx.as_mut_ptr(),
-            tx.version as c_uint,
-            AsRef::<[u8]>::as_ref(&txid).as_ptr(),
-            raw_inputs.as_ptr(),
-            raw_inputs.len() as c_uint,
-            raw_outputs.as_ptr(),
-            raw_outputs.len() as c_uint,
-            tx.lock_time.to_consensus_u32() as c_uint,
-        );
-        let raw_tx = raw_tx.assume_init();
-        c_elements::simplicity_mallocTransaction(&raw_tx)
+        // SAFETY: this is a FFI call and we constructed its argument correctly.
+        c_elements::simplicity_mallocTransaction(&c_raw_tx)
     }
 }