Mint ost prime as base token

contracts/gateway/EIP20CoGateway.sol

@@ -173,7 +173,7 @@ contract EIP20CoGateway is GatewayBase {
         uint256 amount;
 
         /** Address for which the utility tokens will be minted */
-        address beneficiary;
+        address payable beneficiary;
     }
 
     /* public Variables */
@@ -755,7 +755,9 @@ contract EIP20CoGateway is GatewayBase {
      * @param _staker Staker address.
      * @param _stakerNonce Nonce of the staker address.
      * @param _beneficiary The address in the auxiliary chain where the utility
-     *                     tokens will be minted.
+     *                     tokens will be minted. This is payable so that it
+     *                     provides flexibility of transferring base token
+     *                     to account on minting.
      * @param _amount Amount of utility token will be minted.
      * @param _gasPrice Gas price that staker is ready to pay to get the stake
      *                  and mint process done
@@ -770,7 +772,7 @@ contract EIP20CoGateway is GatewayBase {
     function confirmStakeIntent(
         address _staker,
         uint256 _stakerNonce,
-        address _beneficiary,
+        address payable _beneficiary,
         uint256 _amount,
         uint256 _gasPrice,
         uint256 _gasLimit,
@@ -1114,7 +1116,7 @@ contract EIP20CoGateway is GatewayBase {
 
         // Mint token after subtracting reward amount.
         UtilityTokenInterface(utilityToken).increaseSupply(
-            beneficiary_,
+            mint.beneficiary,
             mintedAmount_
         );
 

contracts/gateway/OSTPrime.sol

@@ -31,6 +31,7 @@ import "../lib/SafeMath.sol";
 import "./UtilityToken.sol";
 import "./OSTPrimeConfig.sol";
 import "../lib/IsMemberInterface.sol";
+import "../lib/MutexAddress.sol";
 
 /**
  *  @title OSTPrime contract implements UtilityToken and
@@ -42,7 +43,7 @@ import "../lib/IsMemberInterface.sol";
  *  @dev OSTPrime functions as the base token to pay for gas consumption on the
  *       utility chain.
  */
-contract OSTPrime is UtilityToken, OSTPrimeConfig {
+contract OSTPrime is UtilityToken, OSTPrimeConfig, MutexAddress {
 
     /* Usings */
 
@@ -217,29 +218,47 @@ contract OSTPrime is UtilityToken, OSTPrimeConfig {
     }
 
     /**
-     * @notice Adds number of OST Prime tokens to account balance and increases
-     *         the total token supply. Can be called only when contract is
-     *         initialized and only by CoGateway address.
+     * @notice This method performs following operations:
+     *          - Adds number of OST Prime EIP20 tokens to this contract address.
+     *          - Increases the total token supply.
+     *          - Transfers base token to the beneficiary address.
+     *          It can be called by CoGateway address and when contract is
+     *          initialized.
      *
-     * @dev The parameters _account and _amount should not be zero. This check
+     * @dev The parameter _amount should not be zero. This check
      *      is added in function increaseSupplyInternal.
      *
      * @param _account Account address for which the OST Prime balance will be
-     *                 increased.
+     *                 increased. This is payable so that base token can be
+     *                 transferred to the account.
      * @param _amount Amount of tokens.
      *
      * @return success_ `true` if increase supply is successful, false otherwise.
      */
     function increaseSupply(
-        address _account,
+        address payable _account,
         uint256 _amount
     )
         external
         onlyInitialized
         onlyCoGateway
         returns (bool success_)
     {
-        success_ = increaseSupplyInternal(_account, _amount);
+        require(
+            _account != address(0),
+            "Account address should not be zero."
+        );
+
+        /*
+         * Acquire lock for msg.sender so that this function can only be
+         * executed once in a transaction.
+         */
+        MutexAddress.acquire(msg.sender);
+
+        success_ = increaseSupplyInternal(address(this), _amount);
+        _account.transfer(_amount);
+
+        MutexAddress.release(msg.sender);
     }
 
     /**

contracts/gateway/UtilityToken.sol

@@ -143,12 +143,14 @@ contract UtilityToken is EIP20Token, Organized, UtilityTokenInterface {
      *      is added in function increaseSupplyInternal.
      *
      * @param _account Account address for which the balance will be increased.
+                       This is payable so that it provides flexibility of
+     *                 transferring base token to account on increase supply.
      * @param _amount Amount of tokens.
      *
      * @return success_ `true` if increase supply is successful, false otherwise.
      */
     function increaseSupply(
-        address _account,
+        address payable _account,
         uint256 _amount
     )
         external

contracts/gateway/UtilityTokenInterface.sol

@@ -38,12 +38,14 @@ contract UtilityTokenInterface {
      *      total token supply.
      *
      * @param _account Account address for which the balance will be increased.
+     *                 This is payable so that it provides flexibility of
+     *                 transferring base token to account on increase supply.
      * @param _amount Amount of tokens.
      *
      * @return success_ `true` if increase supply is successful, false otherwise.
      */
     function increaseSupply(
-        address _account,
+        address payable _account,
         uint256 _amount
     )
         external

contracts/lib/MutexAddress.sol

@@ -0,0 +1,78 @@
+pragma solidity ^0.5.0;
+
+// Copyright 2018 OpenST Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ----------------------------------------------------------------------------
+//
+// http://www.simpletoken.org/
+//
+// ----------------------------------------------------------------------------
+
+/** @title MutexAddress contract provide locking mechanism. */
+contract MutexAddress {
+
+    /* Storage */
+
+    /** Mapping of address and lock status. */
+    mapping(address => bool) private locks;
+
+
+    /* Constructor */
+
+    constructor() public
+    { }
+
+    /**
+     * @notice This acquires lock for an account if not already acquired.
+     *          This will revert the transaction if lock is already acquired.
+     *
+     * @param _account Account for which lock acquisition is required.
+     *
+     * @return isAcquired_ `true` on successful lock acquisition, `false` otherwise.
+     */
+    function acquire(address _account)
+        internal
+        returns(bool isAcquired_)
+    {
+        require(
+            locks[_account] == false,
+            "Lock already acquired for the account."
+        );
+
+        locks[_account] = true;
+        isAcquired_ = true;
+    }
+
+    /**
+     * @notice This releases lock for an account if lock is acquired.
+     *          This will revert the transaction if lock is not acquired.
+     *
+     * @param _account Account for which release lock is required.
+     *
+     * @return isReleased_ `true` on successful lock release, `false` otherwise.
+     */
+    function release(address _account)
+        internal
+        returns(bool isReleased_)
+    {
+        require(
+            locks[_account] == true,
+            "Lock is not acquired for the address."
+        );
+
+        locks[_account] = false;
+        isReleased_ = true;
+    }
+}

contracts/test/TestEIP20CoGateway.sol

@@ -132,7 +132,7 @@ contract TestEIP20CoGateway is EIP20CoGateway {
      */
     function setMints(
         bytes32 _messageHash,
-        address _beneficiary,
+        address payable _beneficiary,
         uint256 _amount
     )
         public

contracts/test/TestMutexAddress.sol

@@ -0,0 +1,62 @@
+pragma solidity ^0.5.0;
+
+// Copyright 2018 OpenST Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ----------------------------------------------------------------------------
+//
+// http://www.simpletoken.org/
+//
+// ----------------------------------------------------------------------------
+
+import "../lib/MutexAddress.sol";
+
+/** @title TestMutexAddress contract to test Mutex. */
+contract TestMutexAddress is MutexAddress {
+
+    constructor()
+        MutexAddress()
+        public
+    { }
+
+    /**
+     * @notice This acquires lock for an account if not already acquired.
+     *          This will revert the transaction if lock is already acquired.
+     *
+     * @param _account Account for which lock acquisition is required.
+     *
+     * @return isAcquired_ `true` on successful lock acquisition, `false` otherwise.
+     */
+    function acquireExternal(address _account)
+        external
+        returns(bool success_)
+    {
+        success_ = super.acquire(_account);
+    }
+
+    /**
+     * @notice This releases lock for an account if lock is acquired.
+     *          This will revert the transaction if lock is not acquired.
+     *
+     * @param _account Account for which release lock is required.
+     *
+     * @return isReleased_ `true` on successful lock release, `false` otherwise.
+     */
+    function releaseExternal(address _account)
+        external
+        returns(bool success_)
+    {
+        success_ = super.release(_account);
+    }
+}

test/gateway/ost_prime/decrease_supply.js

@@ -39,7 +39,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
     membersManager,
     coGatewayAddress;
 
-  async function initialize(){
+  async function initialize() {
     await ostPrime.initialize(
       {from: accounts[2], value: TOKENS_MAX}
     );
@@ -71,7 +71,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
     amount = new BN(0);
 
     await Utils.expectRevert(
-      ostPrime.decreaseSupply(amount, { from: coGatewayAddress }),
+      ostPrime.decreaseSupply(amount, {from: coGatewayAddress}),
       'Amount should be greater than zero.',
     );
 
@@ -82,7 +82,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
     await initialize();
 
     await Utils.expectRevert(
-      ostPrime.decreaseSupply(amount, { from: accounts[5] }),
+      ostPrime.decreaseSupply(amount, {from: accounts[5]}),
       'Only CoGateway can call the function.',
     );
 
@@ -91,7 +91,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
   it('should fail when OST Prime contract is not initialized', async function () {
 
     await Utils.expectRevert(
-      ostPrime.decreaseSupply(amount, { from: coGatewayAddress }),
+      ostPrime.decreaseSupply(amount, {from: coGatewayAddress}),
       'Contract is not initialized.',
     );
 
@@ -105,7 +105,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
     amount = new BN(2000);
 
     await Utils.expectRevert(
-      ostPrime.decreaseSupply(amount, { from: coGatewayAddress }),
+      ostPrime.decreaseSupply(amount, {from: coGatewayAddress}),
       'Insufficient balance.',
     );
 
@@ -118,7 +118,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
     amount = new BN(500);
 
     let result = await ostPrime.decreaseSupply.call(
-      amount, { from: coGatewayAddress }
+      amount, {from: coGatewayAddress}
     );
 
     assert.strictEqual(
@@ -127,7 +127,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
       'Contract should return true.',
     );
 
-    await ostPrime.decreaseSupply(amount, { from: coGatewayAddress });
+    await ostPrime.decreaseSupply(amount, {from: coGatewayAddress});
 
     let coGatewayBalance = await ostPrime.balanceOf.call(coGatewayAddress);
 
@@ -152,7 +152,7 @@ contract('OSTPrime.decreaseSupply()', function (accounts) {
 
     let tx = await ostPrime.decreaseSupply(
       amount,
-      { from: coGatewayAddress }
+      {from: coGatewayAddress}
     );
 
     let event = EventDecoder.getEvents(tx, ostPrime);