From cdb14394b4459bd5ebbe865dfce4bc7a8538f037 Mon Sep 17 00:00:00 2001
From: Sowmayjain <champ.sowmay@gmail.com>
Date: Mon, 26 Nov 2018 03:09:47 +0530
Subject: [PATCH] Code optimisation.

---
 contracts/protocols/InstaKyber.sol | 39 ++++++++++++++++++++++++++++--
 contracts/protocols/InstaMaker.sol | 30 ++++++++++++++++++++---
 2 files changed, 64 insertions(+), 5 deletions(-)

diff --git a/contracts/protocols/InstaKyber.sol b/contracts/protocols/InstaKyber.sol
index f10f4a9..914b41e 100644
--- a/contracts/protocols/InstaKyber.sol
+++ b/contracts/protocols/InstaKyber.sol
@@ -1,8 +1,30 @@
 pragma solidity ^0.4.24;
 
-import "openzeppelin-solidity/contracts/math/SafeMath.sol";
-import "openzeppelin-solidity/contracts/token/ERC20/IERC20.sol";
+library SafeMath {
 
+    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
+        if (a == 0) {
+            return 0;
+        }
+        uint256 c = a * b;
+        require(c / a == b, "Assertion Failed");
+        return c;
+    }
+    
+    function div(uint256 a, uint256 b) internal pure returns (uint256) {
+        require(b > 0, "Assertion Failed");
+        uint256 c = a / b;
+        return c;
+    }
+
+}
+
+interface IERC20 {
+    function balanceOf(address who) external view returns (uint256);
+    function transfer(address to, uint256 value) external returns (bool);
+    function approve(address spender, uint256 value) external returns (bool);
+    function transferFrom(address from, address to, uint256 value) external returns (bool);
+}
 
 interface AddressRegistry {
     function getAddr(string name) external view returns(address);
@@ -103,6 +125,17 @@ contract Trade is Registry {
             getAddress("admin")
         );
 
+        // maxDestAmt usecase implementated
+        if (src == getAddress("eth") && address(this).balance > 0) {
+            msg.sender.transfer(address(this).balance);
+        } else {
+            IERC20 srcTkn = IERC20(src);
+            uint srcBal = srcTkn.balanceOf(address(this));
+            if (srcBal > 0) {
+                srcTkn.transfer(msg.sender, srcBal);
+            }
+        }
+
         emit KyberTrade(
             src,
             srcAmt,
@@ -135,4 +168,6 @@ contract InstaKyber is Trade {
         addressRegistry = rAddr;
     }
 
+    function () public payable {}
+
 }
\ No newline at end of file
diff --git a/contracts/protocols/InstaMaker.sol b/contracts/protocols/InstaMaker.sol
index 1c76c91..f490e03 100644
--- a/contracts/protocols/InstaMaker.sol
+++ b/contracts/protocols/InstaMaker.sol
@@ -1,8 +1,31 @@
 pragma solidity 0.4.24;
 
-import "openzeppelin-solidity/contracts/math/SafeMath.sol";
-import "openzeppelin-solidity/contracts/token/ERC20/IERC20.sol";
 
+library SafeMath {
+
+    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
+        if (a == 0) {
+            return 0;
+        }
+        uint256 c = a * b;
+        require(c / a == b, "Assertion Failed");
+        return c;
+    }
+    
+    function div(uint256 a, uint256 b) internal pure returns (uint256) {
+        require(b > 0, "Assertion Failed");
+        uint256 c = a / b;
+        return c;
+    }
+
+}
+
+interface IERC20 {
+    function balanceOf(address who) external view returns (uint256);
+    function transfer(address to, uint256 value) external returns (bool);
+    function approve(address spender, uint256 value) external returns (bool);
+    function transferFrom(address from, address to, uint256 value) external returns (bool);
+}
 
 interface AddressRegistry {
     function getAddr(string name) external view returns(address);
@@ -200,7 +223,6 @@ contract RepayLoan is IssueLoan {
         );
         require(mkrCharged == mkrBought, "ETH not sufficient to cover the MKR fees.");
         if (address(this).balance > 0) {
-            // ether always belong to sender coz no way contract can hold ether
             msg.sender.transfer(address(this).balance);
         }
     }
@@ -252,6 +274,8 @@ contract MoatMaker is BorrowTasks {
         approveERC20();
     }
 
+    function () public payable {}
+
     function freeze(bool stop) public onlyAdmin {
         freezed = stop;
     }