Move LibAddressArray to utils package

8 files changed, 89 insertions, 5 deletions

diff --git a/contracts/utils/contracts/test/TestConstants/TestConstants.sol b/contracts/utils/contracts/test/TestConstants.sol
index 3c852173b..372e0af24 100644
--- a/contracts/utils/contracts/test/TestConstants/TestConstants.sol
+++ b/contracts/utils/contracts/test/TestConstants.sol
@@ -16,9 +16,9 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
-import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
+import "../utils/LibBytes.sol";
 
 
 // solhint-disable max-line-length
diff --git a/contracts/utils/contracts/test/TestLibBytes/TestLibBytes.sol b/contracts/utils/contracts/test/TestLibBytes.sol
index 444a3e717..c1a5866d0 100644
--- a/contracts/utils/contracts/test/TestLibBytes/TestLibBytes.sol
+++ b/contracts/utils/contracts/test/TestLibBytes.sol
@@ -16,9 +16,9 @@
 
 */
 
-pragma solidity 0.4.24;
+pragma solidity ^0.4.24;
 
-import "@0x/contracts-utils/contracts/utils/LibBytes/LibBytes.sol";
+import "../utils/LibBytes.sol";
 
 
 contract TestLibBytes {
diff --git a/contracts/utils/contracts/utils/LibAddressArray.sol b/contracts/utils/contracts/utils/LibAddressArray.sol
new file mode 100644
index 000000000..892c486f1
--- /dev/null
+++ b/contracts/utils/contracts/utils/LibAddressArray.sol
@@ -0,0 +1,84 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  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.
+
+*/
+
+pragma solidity ^0.4.24;
+
+import "./LibBytes.sol";
+
+
+library LibAddressArray {
+
+    /// @dev Append a new address to an array of addresses.
+    ///      The `addressArray` may need to be reallocated to make space
+    ///      for the new address. Because of this we return the resulting
+    ///      memory location of `addressArray`.
+    /// @param addressToAppend  Address to append.
+    /// @return Array of addresses: [... addressArray, addressToAppend]
+    function append(address[] memory addressArray, address addressToAppend) 
+        internal pure
+        returns (address[])
+    {
+        // Get stats on address array and free memory
+        uint256 freeMemPtr = 0;
+        uint256 addressArrayBeginPtr = 0;
+        uint256 addressArrayEndPtr = 0;
+        uint256 addressArrayLength = addressArray.length;
+        uint256 addressArrayMemSizeInBytes = 32 + (32 * addressArrayLength);
+        assembly {
+            freeMemPtr := mload(0x40)
+            addressArrayBeginPtr := addressArray
+            addressArrayEndPtr := add(addressArray, addressArrayMemSizeInBytes)
+        }
+
+        // Cases for `freeMemPtr`:
+        //  `freeMemPtr` == `addressArrayEndPtr`: Nothing occupies memory after `addressArray`
+        //  `freeMemPtr` > `addressArrayEndPtr`: Some value occupies memory after `addressArray`
+        //  `freeMemPtr` < `addressArrayEndPtr`: Memory has not been managed properly.
+        require(
+            freeMemPtr >= addressArrayEndPtr,
+            "INVALID_FREE_MEMORY_PTR"
+        );
+
+        // If free memory begins at the end of `addressArray`
+        // then we can append `addressToAppend` directly.
+        // Otherwise, we must copy the array to free memory
+        // before appending new values to it.
+        if (freeMemPtr > addressArrayEndPtr) {
+            LibBytes.memCopy(freeMemPtr, addressArrayBeginPtr, addressArrayMemSizeInBytes);
+            assembly {
+                addressArray := freeMemPtr
+                addressArrayBeginPtr := addressArray
+            }
+        }
+
+        // Append `addressToAppend`
+        addressArrayLength += 1;
+        addressArrayMemSizeInBytes += 32;
+        addressArrayEndPtr = addressArrayBeginPtr + addressArrayMemSizeInBytes;
+        freeMemPtr = addressArrayEndPtr;
+        assembly {
+            // Store new array length
+            mstore(addressArray, addressArrayLength)
+
+            // Update `freeMemPtr`
+            mstore(0x40, freeMemPtr)
+        }
+        addressArray[addressArrayLength - 1] = addressToAppend;
+        return addressArray;
+    }
+}
diff --git a/contracts/utils/contracts/utils/LibBytes/LibBytes.sol b/contracts/utils/contracts/utils/LibBytes.sol
index 4ee6228d5..4ee6228d5 100644
--- a/contracts/utils/contracts/utils/LibBytes/LibBytes.sol
+++ b/contracts/utils/contracts/utils/LibBytes.sol
diff --git a/contracts/utils/contracts/utils/Ownable/Ownable.sol b/contracts/utils/contracts/utils/Ownable.sol
index aa74a72d2..f67f241a4 100644
--- a/contracts/utils/contracts/utils/Ownable/Ownable.sol
+++ b/contracts/utils/contracts/utils/Ownable.sol
@@ -1,6 +1,6 @@
 pragma solidity ^0.4.24;
 
-import "./IOwnable.sol";
+import "./interfaces/IOwnable.sol";
 
 
 contract Ownable is
diff --git a/contracts/utils/contracts/utils/ReentrancyGuard/ReentrancyGuard.sol b/contracts/utils/contracts/utils/ReentrancyGuard.sol
index 1a02c88a4..1a02c88a4 100644
--- a/contracts/utils/contracts/utils/ReentrancyGuard/ReentrancyGuard.sol
+++ b/contracts/utils/contracts/utils/ReentrancyGuard.sol
diff --git a/contracts/utils/contracts/utils/SafeMath/SafeMath.sol b/contracts/utils/contracts/utils/SafeMath.sol
index d7a4a603e..d7a4a603e 100644
--- a/contracts/utils/contracts/utils/SafeMath/SafeMath.sol
+++ b/contracts/utils/contracts/utils/SafeMath.sol
diff --git a/contracts/utils/contracts/utils/Ownable/IOwnable.sol b/contracts/utils/contracts/utils/interfaces/IOwnable.sol
index c0cbfddfd..c0cbfddfd 100644
--- a/contracts/utils/contracts/utils/Ownable/IOwnable.sol
+++ b/contracts/utils/contracts/utils/interfaces/IOwnable.sol