Merge pull request #844 from zcash/temporary-zcashd-parse-sapling

zcash_primitives: Changes needed for `zcashd` Sapling oxidation

zcash_primitives/CHANGELOG.md

@@ -6,6 +6,15 @@ and this library adheres to Rust's notion of
 [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- `zcash_primitives::transaction`:
+  - `Transaction::temporary_zcashd_read_v5_sapling`
+  - `Transaction::temporary_zcashd_write_v5_sapling`
+- Implementations of `memuse::DynamicUsage` for the following types:
+  - `zcash_primitives::transaction::components::sapling`:
+    - `Bundle<Authorized>`
+    - `SpendDescription<Authorized>`
+
 ### Changed
 - MSRV is now 1.65.0.
 - Bumped dependencies to `secp256k1 0.26`, `hdwallet 0.4`.

zcash_primitives/src/transaction/components/sapling.rs

@@ -192,6 +192,24 @@ impl<A: Authorization> Bundle<A> {
     }
 }
 
+impl DynamicUsage for Bundle<Authorized> {
+    fn dynamic_usage(&self) -> usize {
+        self.shielded_spends.dynamic_usage() + self.shielded_outputs.dynamic_usage()
+    }
+
+    fn dynamic_usage_bounds(&self) -> (usize, Option<usize>) {
+        let bounds = (
+            self.shielded_spends.dynamic_usage_bounds(),
+            self.shielded_outputs.dynamic_usage_bounds(),
+        );
+
+        (
+            bounds.0 .0 + bounds.1 .0,
+            bounds.0 .1.zip(bounds.1 .1).map(|(a, b)| a + b),
+        )
+    }
+}
+
 #[derive(Clone)]
 pub struct SpendDescription<A: Authorization> {
     cv: ValueCommitment,
@@ -263,6 +281,16 @@ impl<A: Authorization> SpendDescription<A> {
     }
 }
 
+impl DynamicUsage for SpendDescription<Authorized> {
+    fn dynamic_usage(&self) -> usize {
+        self.zkproof.dynamic_usage()
+    }
+
+    fn dynamic_usage_bounds(&self) -> (usize, Option<usize>) {
+        self.zkproof.dynamic_usage_bounds()
+    }
+}
+
 /// Consensus rules (§4.4) & (§4.5):
 /// - Canonical encoding is enforced here.
 /// - "Not small order" is enforced here.

zcash_primitives/src/transaction/mod.rs

@@ -730,6 +730,13 @@ impl Transaction {
         Ok((consensus_branch_id, lock_time, expiry_height))
     }
 
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_read_v5_sapling<R: Read>(
+        reader: R,
+    ) -> io::Result<Option<sapling::Bundle<sapling::Authorized>>> {
+        Self::read_v5_sapling(reader)
+    }
+
     #[allow(clippy::redundant_closure)]
     fn read_v5_sapling<R: Read>(
         mut reader: R,
@@ -917,8 +924,23 @@ impl Transaction {
         Ok(())
     }
 
-    pub fn write_v5_sapling<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        if let Some(bundle) = &self.sapling_bundle {
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_write_v5_sapling<W: Write>(
+        sapling_bundle: Option<&sapling::Bundle<sapling::Authorized>>,
+        writer: W,
+    ) -> io::Result<()> {
+        Self::write_v5_sapling_inner(sapling_bundle, writer)
+    }
+
+    pub fn write_v5_sapling<W: Write>(&self, writer: W) -> io::Result<()> {
+        Self::write_v5_sapling_inner(self.sapling_bundle.as_ref(), writer)
+    }
+
+    fn write_v5_sapling_inner<W: Write>(
+        sapling_bundle: Option<&sapling::Bundle<sapling::Authorized>>,
+        mut writer: W,
+    ) -> io::Result<()> {
+        if let Some(bundle) = sapling_bundle {
             Vector::write(&mut writer, bundle.shielded_spends(), |w, e| {
                 e.write_v5_without_witness_data(w)
             })?;