diff options
Diffstat (limited to 'packages/contracts/src/contracts/current/protocol/AssetProxy/MixinERC20Transfer.sol')
-rw-r--r-- | packages/contracts/src/contracts/current/protocol/AssetProxy/MixinERC20Transfer.sol | 113 |
1 files changed, 0 insertions, 113 deletions
diff --git a/packages/contracts/src/contracts/current/protocol/AssetProxy/MixinERC20Transfer.sol b/packages/contracts/src/contracts/current/protocol/AssetProxy/MixinERC20Transfer.sol deleted file mode 100644 index a09db43bd..000000000 --- a/packages/contracts/src/contracts/current/protocol/AssetProxy/MixinERC20Transfer.sol +++ /dev/null @@ -1,113 +0,0 @@ -/* - - 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; -pragma experimental ABIEncoderV2; - -import "../../utils/LibBytes/LibBytes.sol"; -import "../../tokens/ERC20Token/IERC20Token.sol"; - -contract MixinERC20Transfer { - - using LibBytes for bytes; - - /// @dev Internal version of `transferFrom`. - /// @param assetData Encoded byte array. - /// @param from Address to transfer asset from. - /// @param to Address to transfer asset to. - /// @param amount Amount of asset to transfer. - function transferFromInternal( - bytes memory assetData, - address from, - address to, - uint256 amount - ) - internal - { - // Decode asset data. - address token = assetData.readAddress(16); - - // Transfer tokens. - // We do a raw call so we can check the success separate - // from the return data. - // We construct calldata for the `token.transferFrom` ABI. - // The layout of this calldata is in the table below. - // - // | Area | Offset | Length | Contents | - // |----------|--------|---------|-------------------------------------| - // | Header | 0 | 4 | function selector | - // | Params | | 3 * 32 | function parameters: | - // | | 4 | | 1. from | - // | | 36 | | 2. to | - // | | 68 | | 3. amount | - - bytes4 transferFromSelector = IERC20Token(token).transferFrom.selector; - bool success; - assembly { - /////// Setup State /////// - // `cdStart` is the start of the calldata for `token.transferFrom` (equal to free memory ptr). - let cdStart := mload(64) - - /////// Setup Header Area /////// - // This area holds the 4-byte `transferFromSelector`. - // Any trailing data in transferFromSelector will be - // overwritten in the next `mstore` call. - mstore(cdStart, transferFromSelector) - - /////// Setup Params Area /////// - // Each parameter is padded to 32-bytes. - // The entire Params Area is 96 bytes. - // A 20-byte mask is applied to addresses to - // zero-out the unused bytes. - mstore(add(cdStart, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) - mstore(add(cdStart, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) - mstore(add(cdStart, 68), amount) - - /////// Call `token.transferFrom` using the calldata /////// - success := call( - gas, // forward all gas - token, // call address of token contract - 0, // don't send any ETH - cdStart, // pointer to start of input - 100, // length of input - cdStart, // write output over input - 32 // output size should be 32 bytes - ) - - /////// Check return data. /////// - // If there is no return data, we assume the token incorrectly - // does not return a bool. In this case we expect it to revert - // on failure, which was handled above. - // If the token does return data, we require that it is a single - // nonzero 32 bytes value. - // So the transfer succeeded if the call succeeded and either - // returned nothing, or returned a non-zero 32 byte value. - success := and(success, or( - iszero(returndatasize), - and( - eq(returndatasize, 32), - gt(mload(cdStart), 0) - ) - )) - } - require( - success, - "TRANSFER_FAILED" - ); - } -} |