wallet: add ReleaseInputs

wallet/wallet.go

@@ -243,14 +243,14 @@ func (sw *SingleAddressWallet) SpendableOutputs() ([]types.SiacoinElement, error
 // transaction. If necessary, a change output will also be added. The inputs
 // will not be available to future calls to FundTransaction unless ReleaseInputs
 // is called.
-func (sw *SingleAddressWallet) FundTransaction(txn *types.Transaction, amount types.Currency, useUnconfirmed bool) ([]types.Hash256, func(), error) {
+func (sw *SingleAddressWallet) FundTransaction(txn *types.Transaction, amount types.Currency, useUnconfirmed bool) ([]types.Hash256, error) {
 	if amount.IsZero() {
-		return nil, func() {}, nil
+		return nil, nil
 	}
 
 	utxos, err := sw.store.UnspentSiacoinElements()
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 
 	tpoolSpent := make(map[types.Hash256]bool)
@@ -327,10 +327,10 @@ func (sw *SingleAddressWallet) FundTransaction(txn *types.Transaction, amount ty
 
 		if inputSum.Cmp(amount) < 0 {
 			// still not enough funds
-			return nil, nil, ErrNotEnoughFunds
+			return nil, ErrNotEnoughFunds
 		}
 	} else if inputSum.Cmp(amount) < 0 {
-		return nil, nil, ErrNotEnoughFunds
+		return nil, ErrNotEnoughFunds
 	}
 
 	// check if remaining utxos should be defragged
@@ -371,14 +371,7 @@ func (sw *SingleAddressWallet) FundTransaction(txn *types.Transaction, amount ty
 		sw.locked[sce.ID] = time.Now().Add(sw.cfg.ReservationDuration)
 	}
 
-	release := func() {
-		sw.mu.Lock()
-		defer sw.mu.Unlock()
-		for _, id := range toSign {
-			delete(sw.locked, id)
-		}
-	}
-	return toSign, release, nil
+	return toSign, nil
 }
 
 // SignTransaction adds a signature to each of the specified inputs.
@@ -576,6 +569,19 @@ func (sw *SingleAddressWallet) Redistribute(outputs int, amount, feePerByte type
 	return
 }
 
+// ReleaseInputs is a helper function that releases the inputs of txn for use in
+// other transactions. It should only be called on transactions that are invalid
+// or will never be broadcast.
+func (sw *SingleAddressWallet) ReleaseInputs(txns ...types.Transaction) {
+	sw.mu.Lock()
+	defer sw.mu.Unlock()
+	for _, txn := range txns {
+		for _, in := range txn.SiacoinInputs {
+			delete(sw.locked, types.Hash256(in.ParentID))
+		}
+	}
+}
+
 // IsRelevantTransaction returns true if the v1 transaction is relevant to the
 // address
 func IsRelevantTransaction(txn types.Transaction, addr types.Address) bool {