feature/match-trade

contracts/Exchange.sol

@@ -56,7 +56,27 @@ contract Exchange is Ownable, ExchangeInterface {
     /// @param signature Signed order along with signature mode.
     /// @param maxFillAmount Maximum amount of the order to be filled.
     function trade(address[3] addresses, uint[4] values, bytes signature, uint maxFillAmount) external {
-        exchange.trade(OrderLibrary.createOrder(addresses, values), msg.sender, signature, maxFillAmount);
+        exchange.trade(OrderLibrary.createOrder(addresses, values), msg.sender, signature, maxFillAmount, true);
+    }
+
+    function matchTrade(address[3][2] addresses, uint[4][2] values, bytes leftSignature, bytes rightSignature)
+        external
+    {
+        OrderLibrary.Order memory left = OrderLibrary.createOrder(addresses[0], values[0]);
+        OrderLibrary.Order memory right = OrderLibrary.createOrder(addresses[1], values[1]);
+
+        require(left.maker != right.maker);
+        require(left.makerToken == right.takerToken);
+        require(left.takerToken == right.makerToken);
+
+        bytes32 leftHash = left.hash();
+        bytes32 rightHash = right.hash();
+
+        require(exchange.canTrade(left, leftSignature, leftHash));
+        require(exchange.canTrade(right, rightSignature, rightHash));
+
+        exchange.trade(left, right.maker, leftSignature, exchange.availableAmount(right, rightHash), true);
+        exchange.trade(right, left.maker, rightSignature, exchange.availableAmount(left, leftHash), false);
     }
 
     /// @dev Cancels an order.

contracts/Libraries/ExchangeLibrary.sol

@@ -45,7 +45,8 @@ library ExchangeLibrary {
         OrderLibrary.Order memory order,
         address taker,
         bytes signature,
-        uint maxFillAmount
+        uint maxFillAmount,
+        bool chargeFees
     )
         internal
     {
@@ -63,7 +64,7 @@ library ExchangeLibrary {
         uint makeAmount = order.makerTokenAmount.mul(fillAmount).div(order.takerTokenAmount);
         uint tradeTakerFee = makeAmount.mul(self.takerFee).div(1 ether);
 
-        if (tradeTakerFee > 0) {
+        if (tradeTakerFee > 0 && chargeFees) {
             self.vault.transfer(order.makerToken, order.maker, self.feeAccount, tradeTakerFee);
         }