loopin: restore abandon chan on restart

client.go

@@ -381,6 +381,12 @@ func (s *Client) resumeSwaps(ctx context.Context,
 			continue
 		}
 
+		// Store the swap's abandon channel so that the client can
+		// abandon the swap by providing the swap hash.
+		s.executor.Lock()
+		s.abandonChans[swap.hash] = swap.abandonChan
+		s.executor.Unlock()
+
 		s.executor.initiateSwap(ctx, swap)
 	}
 }

loopin.go

@@ -421,6 +421,10 @@ func resumeLoopInSwap(_ context.Context, cfg *swapConfig,
 		swap.cost = lastUpdate.Cost
 	}
 
+	// Upon restoring the swap we also need to assign a new abandon channel
+	// that the client can use to signal that the swap should be abandoned.
+	swap.abandonChan = make(chan struct{}, 1)
+
 	return swap, nil
 }