Experimental Feature

contracts/MultiSigWalletWithExternalDailyLimit

@@ -0,0 +1,112 @@
+pragma solidity ^0.4.15;
+import "./MultiSigWallet.sol";
+
+interface DailyLimit {
+
+  function limit() returns (uint256);
+
+}
+
+
+/// @title Multisignature wallet with daily limit - Allows an owner to withdraw a daily limit without multisig.
+/// @author Stefan George - <[email protected]>
+contract MultiSigWalletWithExternalDailyLimit is MultiSigWallet {
+
+    /*
+     *  Events
+     */
+    event DailyLimitChange(DailyLimit dailyLimit);
+
+    /*
+     *  Storage
+     */
+    DailyLimit public dailyLimit;
+    uint public lastDay;
+    uint public spentToday;
+
+    /*
+     * Public functions
+     */
+    /// @dev Contract constructor sets initial owners, required number of confirmations and daily withdraw limit.
+    /// @param _owners List of initial owners.
+    /// @param _required Number of required confirmations.
+    /// @param _dailyLimit An external address providing the daily limit.
+    function MultiSigWalletWithDailyLimit(address[] _owners, uint _required, DailyLimit _dailyLimit)
+        public
+        MultiSigWallet(_owners, _required)
+    {
+        dailyLimit = _dailyLimit;
+    }
+
+    /// @dev Allows to change the daily limit. Transaction has to be sent by wallet.
+    /// @param _dailyLimit Amount in wei.
+    function changeDailyLimit(DailyLimit _dailyLimit)
+        public
+        onlyWallet
+    {
+        dailyLimit = _dailyLimit;
+        DailyLimitChange(_dailyLimit);
+    }
+
+    /// @dev Allows anyone to execute a confirmed transaction or ether withdraws until daily limit is reached.
+    /// @param transactionId Transaction ID.
+    function executeTransaction(uint transactionId)
+        public
+        ownerExists(msg.sender)
+        confirmed(transactionId, msg.sender)
+        notExecuted(transactionId)
+    {
+        Transaction storage txn = transactions[transactionId];
+        bool _confirmed = isConfirmed(transactionId);
+        if (_confirmed || txn.data.length == 0 && isUnderLimit(txn.value)) {
+            txn.executed = true;
+            if (!_confirmed)
+                spentToday += txn.value;
+            if (external_call(txn.destination, txn.value, txn.data.length, txn.data))
+                Execution(transactionId);
+            else {
+                ExecutionFailure(transactionId);
+                txn.executed = false;
+                if (!_confirmed)
+                    spentToday -= txn.value;
+            }
+        }
+    }
+
+    /*
+     * Internal functions
+     */
+    /// @dev Returns if amount is within daily limit and resets spentToday after one day.
+    /// @param amount Amount to withdraw.
+    /// @return Returns if amount is under daily limit.
+    function isUnderLimit(uint amount)
+        internal
+        returns (bool)
+    {
+        if (now > lastDay + 24 hours) {
+            lastDay = now;
+            spentToday = 0;
+        }
+        if (spentToday + amount > dailyLimit.limit() || spentToday + amount < spentToday)
+            return false;
+        return true;
+    }
+
+    /*
+     * Web3 call functions
+     */
+    /// @dev Returns maximum withdraw amount.
+    /// @return Returns amount.
+    function calcMaxWithdraw()
+        public
+        constant
+        returns (uint)
+    {
+        limit = dailyLimit.limit();
+        if (now > lastDay + 24 hours)
+            return limit;
+        if (limit < spentToday)
+            return 0;
+        return limit - spentToday;
+    }
+}