New: Add logic for deleting UTXOs above a given height.

src/main/java/cash/z/ecc/android/sdk/jni/RustBackend.kt

@@ -138,6 +138,11 @@ class RustBackend private constructor() : RustBackendWelding {
         height: Int
     ): Boolean = putUtxo(pathDataDb, tAddress, txId, index, script, value, height)
 
+    override fun clearUtxos(
+        tAddress: String,
+        aboveHeight: Int,
+    ): Boolean = clearUtxos(pathDataDb, tAddress, aboveHeight)
+
     override fun getDownloadedUtxoBalance(address: String): CompactBlockProcessor.WalletBalance {
         val verified = getVerifiedTransparentBalance(pathDataDb, address)
         val total = getTotalTransparentBalance(pathDataDb, address)
@@ -306,6 +311,12 @@ class RustBackend private constructor() : RustBackendWelding {
             height: Int
         ): Boolean
 
+        @JvmStatic private external fun clearUtxos(
+            dbDataPath: String,
+            tAddress: String,
+            aboveHeight: Int,
+        ): Boolean
+
         @JvmStatic private external fun getVerifiedTransparentBalance(
             pathDataDb: String,
             taddr: String

src/main/java/cash/z/ecc/android/sdk/jni/RustBackendWelding.kt

@@ -1,6 +1,7 @@
 package cash.z.ecc.android.sdk.jni
 
 import cash.z.ecc.android.sdk.block.CompactBlockProcessor
+import cash.z.ecc.android.sdk.ext.ZcashSdk
 
 /**
  * Contract defining the exposed capabilities of the Rust backend.
@@ -70,6 +71,8 @@ interface RustBackendWelding {
         height: Int
     ): Boolean
 
+    fun clearUtxos(tAddress: String, aboveHeight: Int = ZcashSdk.SAPLING_ACTIVATION_HEIGHT - 1): Boolean
+
     fun getDownloadedUtxoBalance(address: String): CompactBlockProcessor.WalletBalance
 
     // Implemented by `DerivationTool`

src/main/rust/lib.rs

@@ -38,7 +38,10 @@ use zcash_client_sqlite::{
     BlockDB,
     error::SqliteClientError,
     NoteId,
-    wallet::init::{init_accounts_table, init_blocks_table, init_wallet_db}, wallet::put_received_transparent_utxo, WalletDB,
+    wallet::init::{init_accounts_table, init_blocks_table, init_wallet_db},
+    wallet::{put_received_transparent_utxo, delete_utxos_above},
+    wallet::rewind_to_height,
+    WalletDB,
 };
 use zcash_primitives::{
     block::BlockHash,
@@ -776,6 +779,31 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_jni_RustBackend_putUtxo(
     unwrap_exc_or(&env, res, JNI_FALSE)
 }
 
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_jni_RustBackend_clearUtxos(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    taddress: JString<'_>,
+    above_height: jint,
+) -> jint {
+    let res = panic::catch_unwind(|| {
+    let db_data = wallet_db(&env, NETWORK, db_data)?;
+    let mut db_data = db_data.get_update_ops()?;
+    let addr = utils::java_string_to_rust(&env, taddress);
+    let taddress = TransparentAddress::decode(&NETWORK, &addr).unwrap();
+    let height = BlockHeight::from(above_height as u32);
+
+    debug!("clearing UTXOs that were found above height: {}", above_height);
+        match delete_utxos_above(&mut db_data, &taddress, height) {
+            Ok(rows) => Ok(rows as i32),
+            Err(e) => Err(format_err!("Error while clearing UTXOs: {}", e)),
+        }
+    });
+    unwrap_exc_or(&env, res, -1)
+}
+
 // ADDED BY ANDROID
 #[no_mangle]
 pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_jni_RustBackend_scanBlockBatch(