Contract Source Code:
File 1 of 1 : Synth
/*
⚠⚠⚠ WARNING WARNING WARNING ⚠⚠⚠
This is a TARGET contract - DO NOT CONNECT TO IT DIRECTLY IN YOUR CONTRACTS or DAPPS!
This contract has an associated PROXY that MUST be used for all integrations - this TARGET will be REPLACED in an upcoming Synthetix release!
The proxy can be found by looking up the PROXY property on this contract.
*//*
____ __ __ __ _
/ __/__ __ ___ / /_ / / ___ / /_ (_)__ __
_\ \ / // // _ \/ __// _ \/ -_)/ __// / \ \ /
/___/ \_, //_//_/\__//_//_/\__/ \__//_/ /_\_\
/___/
* Synthetix: Synth.sol
*
* Latest source (may be newer): https://github.com/Synthetixio/synthetix/blob/master/contracts/Synth.sol
* Docs: https://docs.synthetix.io/contracts/Synth
*
* Contract Dependencies:
* - ExternStateToken
* - MixinResolver
* - Owned
* - Proxyable
* - SelfDestructible
* - State
* Libraries:
* - SafeDecimalMath
* - SafeMath
*
* MIT License
* ===========
*
* Copyright (c) 2020 Synthetix
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
*/
/* ===============================================
* Flattened with Solidifier by Coinage
*
* https://solidifier.coina.ge
* ===============================================
*/
pragma solidity ^0.4.24;
/**
* @title SafeMath
* @dev Math operations with safety checks that revert on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, reverts on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0); // Solidity only automatically asserts when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a);
uint256 c = a - b;
return c;
}
/**
* @dev Adds two numbers, reverts on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
/**
* @dev Divides two numbers and returns the remainder (unsigned integer modulo),
* reverts when dividing by zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0);
return a % b;
}
}
// https://docs.synthetix.io/contracts/SafeDecimalMath
library SafeDecimalMath {
using SafeMath for uint;
/* Number of decimal places in the representations. */
uint8 public constant decimals = 18;
uint8 public constant highPrecisionDecimals = 27;
/* The number representing 1.0. */
uint public constant UNIT = 10**uint(decimals);
/* The number representing 1.0 for higher fidelity numbers. */
uint public constant PRECISE_UNIT = 10**uint(highPrecisionDecimals);
uint private constant UNIT_TO_HIGH_PRECISION_CONVERSION_FACTOR = 10**uint(highPrecisionDecimals - decimals);
/**
* @return Provides an interface to UNIT.
*/
function unit() external pure returns (uint) {
return UNIT;
}
/**
* @return Provides an interface to PRECISE_UNIT.
*/
function preciseUnit() external pure returns (uint) {
return PRECISE_UNIT;
}
/**
* @return The result of multiplying x and y, interpreting the operands as fixed-point
* decimals.
*
* @dev A unit factor is divided out after the product of x and y is evaluated,
* so that product must be less than 2**256. As this is an integer division,
* the internal division always rounds down. This helps save on gas. Rounding
* is more expensive on gas.
*/
function multiplyDecimal(uint x, uint y) internal pure returns (uint) {
/* Divide by UNIT to remove the extra factor introduced by the product. */
return x.mul(y) / UNIT;
}
/**
* @return The result of safely multiplying x and y, interpreting the operands
* as fixed-point decimals of the specified precision unit.
*
* @dev The operands should be in the form of a the specified unit factor which will be
* divided out after the product of x and y is evaluated, so that product must be
* less than 2**256.
*
* Unlike multiplyDecimal, this function rounds the result to the nearest increment.
* Rounding is useful when you need to retain fidelity for small decimal numbers
* (eg. small fractions or percentages).
*/
function _multiplyDecimalRound(uint x, uint y, uint precisionUnit) private pure returns (uint) {
/* Divide by UNIT to remove the extra factor introduced by the product. */
uint quotientTimesTen = x.mul(y) / (precisionUnit / 10);
if (quotientTimesTen % 10 >= 5) {
quotientTimesTen += 10;
}
return quotientTimesTen / 10;
}
/**
* @return The result of safely multiplying x and y, interpreting the operands
* as fixed-point decimals of a precise unit.
*
* @dev The operands should be in the precise unit factor which will be
* divided out after the product of x and y is evaluated, so that product must be
* less than 2**256.
*
* Unlike multiplyDecimal, this function rounds the result to the nearest increment.
* Rounding is useful when you need to retain fidelity for small decimal numbers
* (eg. small fractions or percentages).
*/
function multiplyDecimalRoundPrecise(uint x, uint y) internal pure returns (uint) {
return _multiplyDecimalRound(x, y, PRECISE_UNIT);
}
/**
* @return The result of safely multiplying x and y, interpreting the operands
* as fixed-point decimals of a standard unit.
*
* @dev The operands should be in the standard unit factor which will be
* divided out after the product of x and y is evaluated, so that product must be
* less than 2**256.
*
* Unlike multiplyDecimal, this function rounds the result to the nearest increment.
* Rounding is useful when you need to retain fidelity for small decimal numbers
* (eg. small fractions or percentages).
*/
function multiplyDecimalRound(uint x, uint y) internal pure returns (uint) {
return _multiplyDecimalRound(x, y, UNIT);
}
/**
* @return The result of safely dividing x and y. The return value is a high
* precision decimal.
*
* @dev y is divided after the product of x and the standard precision unit
* is evaluated, so the product of x and UNIT must be less than 2**256. As
* this is an integer division, the result is always rounded down.
* This helps save on gas. Rounding is more expensive on gas.
*/
function divideDecimal(uint x, uint y) internal pure returns (uint) {
/* Reintroduce the UNIT factor that will be divided out by y. */
return x.mul(UNIT).div(y);
}
/**
* @return The result of safely dividing x and y. The return value is as a rounded
* decimal in the precision unit specified in the parameter.
*
* @dev y is divided after the product of x and the specified precision unit
* is evaluated, so the product of x and the specified precision unit must
* be less than 2**256. The result is rounded to the nearest increment.
*/
function _divideDecimalRound(uint x, uint y, uint precisionUnit) private pure returns (uint) {
uint resultTimesTen = x.mul(precisionUnit * 10).div(y);
if (resultTimesTen % 10 >= 5) {
resultTimesTen += 10;
}
return resultTimesTen / 10;
}
/**
* @return The result of safely dividing x and y. The return value is as a rounded
* standard precision decimal.
*
* @dev y is divided after the product of x and the standard precision unit
* is evaluated, so the product of x and the standard precision unit must
* be less than 2**256. The result is rounded to the nearest increment.
*/
function divideDecimalRound(uint x, uint y) internal pure returns (uint) {
return _divideDecimalRound(x, y, UNIT);
}
/**
* @return The result of safely dividing x and y. The return value is as a rounded
* high precision decimal.
*
* @dev y is divided after the product of x and the high precision unit
* is evaluated, so the product of x and the high precision unit must
* be less than 2**256. The result is rounded to the nearest increment.
*/
function divideDecimalRoundPrecise(uint x, uint y) internal pure returns (uint) {
return _divideDecimalRound(x, y, PRECISE_UNIT);
}
/**
* @dev Convert a standard decimal representation to a high precision one.
*/
function decimalToPreciseDecimal(uint i) internal pure returns (uint) {
return i.mul(UNIT_TO_HIGH_PRECISION_CONVERSION_FACTOR);
}
/**
* @dev Convert a high precision decimal to a standard decimal representation.
*/
function preciseDecimalToDecimal(uint i) internal pure returns (uint) {
uint quotientTimesTen = i / (UNIT_TO_HIGH_PRECISION_CONVERSION_FACTOR / 10);
if (quotientTimesTen % 10 >= 5) {
quotientTimesTen += 10;
}
return quotientTimesTen / 10;
}
}
// https://docs.synthetix.io/contracts/Owned
contract Owned {
address public owner;
address public nominatedOwner;
/**
* @dev Owned Constructor
*/
constructor(address _owner) public {
require(_owner != address(0), "Owner address cannot be 0");
owner = _owner;
emit OwnerChanged(address(0), _owner);
}
/**
* @notice Nominate a new owner of this contract.
* @dev Only the current owner may nominate a new owner.
*/
function nominateNewOwner(address _owner) external onlyOwner {
nominatedOwner = _owner;
emit OwnerNominated(_owner);
}
/**
* @notice Accept the nomination to be owner.
*/
function acceptOwnership() external {
require(msg.sender == nominatedOwner, "You must be nominated before you can accept ownership");
emit OwnerChanged(owner, nominatedOwner);
owner = nominatedOwner;
nominatedOwner = address(0);
}
modifier onlyOwner {
require(msg.sender == owner, "Only the contract owner may perform this action");
_;
}
event OwnerNominated(address newOwner);
event OwnerChanged(address oldOwner, address newOwner);
}
// https://docs.synthetix.io/contracts/SelfDestructible
contract SelfDestructible is Owned {
uint public initiationTime;
bool public selfDestructInitiated;
address public selfDestructBeneficiary;
uint public constant SELFDESTRUCT_DELAY = 4 weeks;
/**
* @dev Constructor
* @param _owner The account which controls this contract.
*/
constructor(address _owner) public Owned(_owner) {
require(_owner != address(0), "Owner must not be zero");
selfDestructBeneficiary = _owner;
emit SelfDestructBeneficiaryUpdated(_owner);
}
/**
* @notice Set the beneficiary address of this contract.
* @dev Only the contract owner may call this. The provided beneficiary must be non-null.
* @param _beneficiary The address to pay any eth contained in this contract to upon self-destruction.
*/
function setSelfDestructBeneficiary(address _beneficiary) external onlyOwner {
require(_beneficiary != address(0), "Beneficiary must not be zero");
selfDestructBeneficiary = _beneficiary;
emit SelfDestructBeneficiaryUpdated(_beneficiary);
}
/**
* @notice Begin the self-destruction counter of this contract.
* Once the delay has elapsed, the contract may be self-destructed.
* @dev Only the contract owner may call this.
*/
function initiateSelfDestruct() external onlyOwner {
initiationTime = now;
selfDestructInitiated = true;
emit SelfDestructInitiated(SELFDESTRUCT_DELAY);
}
/**
* @notice Terminate and reset the self-destruction timer.
* @dev Only the contract owner may call this.
*/
function terminateSelfDestruct() external onlyOwner {
initiationTime = 0;
selfDestructInitiated = false;
emit SelfDestructTerminated();
}
/**
* @notice If the self-destruction delay has elapsed, destroy this contract and
* remit any ether it owns to the beneficiary address.
* @dev Only the contract owner may call this.
*/
function selfDestruct() external onlyOwner {
require(selfDestructInitiated, "Self Destruct not yet initiated");
require(initiationTime + SELFDESTRUCT_DELAY < now, "Self destruct delay not met");
address beneficiary = selfDestructBeneficiary;
emit SelfDestructed(beneficiary);
selfdestruct(beneficiary);
}
event SelfDestructTerminated();
event SelfDestructed(address beneficiary);
event SelfDestructInitiated(uint selfDestructDelay);
event SelfDestructBeneficiaryUpdated(address newBeneficiary);
}
// https://docs.synthetix.io/contracts/State
contract State is Owned {
// the address of the contract that can modify variables
// this can only be changed by the owner of this contract
address public associatedContract;
constructor(address _owner, address _associatedContract) public Owned(_owner) {
associatedContract = _associatedContract;
emit AssociatedContractUpdated(_associatedContract);
}
/* ========== SETTERS ========== */
// Change the associated contract to a new address
function setAssociatedContract(address _associatedContract) external onlyOwner {
associatedContract = _associatedContract;
emit AssociatedContractUpdated(_associatedContract);
}
/* ========== MODIFIERS ========== */
modifier onlyAssociatedContract {
require(msg.sender == associatedContract, "Only the associated contract can perform this action");
_;
}
/* ========== EVENTS ========== */
event AssociatedContractUpdated(address associatedContract);
}
// https://docs.synthetix.io/contracts/TokenState
contract TokenState is State {
/* ERC20 fields. */
mapping(address => uint) public balanceOf;
mapping(address => mapping(address => uint)) public allowance;
/**
* @dev Constructor
* @param _owner The address which controls this contract.
* @param _associatedContract The ERC20 contract whose state this composes.
*/
constructor(address _owner, address _associatedContract) public State(_owner, _associatedContract) {}
/* ========== SETTERS ========== */
/**
* @notice Set ERC20 allowance.
* @dev Only the associated contract may call this.
* @param tokenOwner The authorising party.
* @param spender The authorised party.
* @param value The total value the authorised party may spend on the
* authorising party's behalf.
*/
function setAllowance(address tokenOwner, address spender, uint value) external onlyAssociatedContract {
allowance[tokenOwner][spender] = value;
}
/**
* @notice Set the balance in a given account
* @dev Only the associated contract may call this.
* @param account The account whose value to set.
* @param value The new balance of the given account.
*/
function setBalanceOf(address account, uint value) external onlyAssociatedContract {
balanceOf[account] = value;
}
}
// https://docs.synthetix.io/contracts/Proxy
contract Proxy is Owned {
Proxyable public target;
bool public useDELEGATECALL;
constructor(address _owner) public Owned(_owner) {}
function setTarget(Proxyable _target) external onlyOwner {
target = _target;
emit TargetUpdated(_target);
}
function setUseDELEGATECALL(bool value) external onlyOwner {
useDELEGATECALL = value;
}
function _emit(bytes callData, uint numTopics, bytes32 topic1, bytes32 topic2, bytes32 topic3, bytes32 topic4)
external
onlyTarget
{
uint size = callData.length;
bytes memory _callData = callData;
assembly {
/* The first 32 bytes of callData contain its length (as specified by the abi).
* Length is assumed to be a uint256 and therefore maximum of 32 bytes
* in length. It is also leftpadded to be a multiple of 32 bytes.
* This means moving call_data across 32 bytes guarantees we correctly access
* the data itself. */
switch numTopics
case 0 {
log0(add(_callData, 32), size)
}
case 1 {
log1(add(_callData, 32), size, topic1)
}
case 2 {
log2(add(_callData, 32), size, topic1, topic2)
}
case 3 {
log3(add(_callData, 32), size, topic1, topic2, topic3)
}
case 4 {
log4(add(_callData, 32), size, topic1, topic2, topic3, topic4)
}
}
}
function() external payable {
if (useDELEGATECALL) {
assembly {
/* Copy call data into free memory region. */
let free_ptr := mload(0x40)
calldatacopy(free_ptr, 0, calldatasize)
/* Forward all gas and call data to the target contract. */
let result := delegatecall(gas, sload(target_slot), free_ptr, calldatasize, 0, 0)
returndatacopy(free_ptr, 0, returndatasize)
/* Revert if the call failed, otherwise return the result. */
if iszero(result) {
revert(free_ptr, returndatasize)
}
return(free_ptr, returndatasize)
}
} else {
/* Here we are as above, but must send the messageSender explicitly
* since we are using CALL rather than DELEGATECALL. */
target.setMessageSender(msg.sender);
assembly {
let free_ptr := mload(0x40)
calldatacopy(free_ptr, 0, calldatasize)
/* We must explicitly forward ether to the underlying contract as well. */
let result := call(gas, sload(target_slot), callvalue, free_ptr, calldatasize, 0, 0)
returndatacopy(free_ptr, 0, returndatasize)
if iszero(result) {
revert(free_ptr, returndatasize)
}
return(free_ptr, returndatasize)
}
}
}
modifier onlyTarget {
require(Proxyable(msg.sender) == target, "Must be proxy target");
_;
}
event TargetUpdated(Proxyable newTarget);
}
// https://docs.synthetix.io/contracts/Proxyable
contract Proxyable is Owned {
// This contract should be treated like an abstract contract
/* The proxy this contract exists behind. */
Proxy public proxy;
Proxy public integrationProxy;
/* The caller of the proxy, passed through to this contract.
* Note that every function using this member must apply the onlyProxy or
* optionalProxy modifiers, otherwise their invocations can use stale values. */
address public messageSender;
constructor(address _proxy, address _owner) public Owned(_owner) {
proxy = Proxy(_proxy);
emit ProxyUpdated(_proxy);
}
function setProxy(address _proxy) external onlyOwner {
proxy = Proxy(_proxy);
emit ProxyUpdated(_proxy);
}
function setIntegrationProxy(address _integrationProxy) external onlyOwner {
integrationProxy = Proxy(_integrationProxy);
}
function setMessageSender(address sender) external onlyProxy {
messageSender = sender;
}
modifier onlyProxy {
require(Proxy(msg.sender) == proxy || Proxy(msg.sender) == integrationProxy, "Only the proxy can call");
_;
}
modifier optionalProxy {
if (Proxy(msg.sender) != proxy && Proxy(msg.sender) != integrationProxy && messageSender != msg.sender) {
messageSender = msg.sender;
}
_;
}
modifier optionalProxy_onlyOwner {
if (Proxy(msg.sender) != proxy && Proxy(msg.sender) != integrationProxy && messageSender != msg.sender) {
messageSender = msg.sender;
}
require(messageSender == owner, "Owner only function");
_;
}
event ProxyUpdated(address proxyAddress);
}
// https://docs.synthetix.io/contracts/ExternStateToken
contract ExternStateToken is SelfDestructible, Proxyable {
using SafeMath for uint;
using SafeDecimalMath for uint;
/* ========== STATE VARIABLES ========== */
/* Stores balances and allowances. */
TokenState public tokenState;
/* Other ERC20 fields. */
string public name;
string public symbol;
uint public totalSupply;
uint8 public decimals;
/**
* @dev Constructor.
* @param _proxy The proxy associated with this contract.
* @param _name Token's ERC20 name.
* @param _symbol Token's ERC20 symbol.
* @param _totalSupply The total supply of the token.
* @param _tokenState The TokenState contract address.
* @param _owner The owner of this contract.
*/
constructor(
address _proxy,
TokenState _tokenState,
string _name,
string _symbol,
uint _totalSupply,
uint8 _decimals,
address _owner
) public SelfDestructible(_owner) Proxyable(_proxy, _owner) {
tokenState = _tokenState;
name = _name;
symbol = _symbol;
totalSupply = _totalSupply;
decimals = _decimals;
}
/* ========== VIEWS ========== */
/**
* @notice Returns the ERC20 allowance of one party to spend on behalf of another.
* @param owner The party authorising spending of their funds.
* @param spender The party spending tokenOwner's funds.
*/
function allowance(address owner, address spender) public view returns (uint) {
return tokenState.allowance(owner, spender);
}
/**
* @notice Returns the ERC20 token balance of a given account.
*/
function balanceOf(address account) public view returns (uint) {
return tokenState.balanceOf(account);
}
/* ========== MUTATIVE FUNCTIONS ========== */
/**
* @notice Set the address of the TokenState contract.
* @dev This can be used to "pause" transfer functionality, by pointing the tokenState at 0x000..
* as balances would be unreachable.
*/
function setTokenState(TokenState _tokenState) external optionalProxy_onlyOwner {
tokenState = _tokenState;
emitTokenStateUpdated(_tokenState);
}
function _internalTransfer(address from, address to, uint value) internal returns (bool) {
/* Disallow transfers to irretrievable-addresses. */
require(to != address(0) && to != address(this) && to != address(proxy), "Cannot transfer to this address");
// Insufficient balance will be handled by the safe subtraction.
tokenState.setBalanceOf(from, tokenState.balanceOf(from).sub(value));
tokenState.setBalanceOf(to, tokenState.balanceOf(to).add(value));
// Emit a standard ERC20 transfer event
emitTransfer(from, to, value);
return true;
}
/**
* @dev Perform an ERC20 token transfer. Designed to be called by transfer functions possessing
* the onlyProxy or optionalProxy modifiers.
*/
function _transfer_byProxy(address from, address to, uint value) internal returns (bool) {
return _internalTransfer(from, to, value);
}
/**
* @dev Perform an ERC20 token transferFrom. Designed to be called by transferFrom functions
* possessing the optionalProxy or optionalProxy modifiers.
*/
function _transferFrom_byProxy(address sender, address from, address to, uint value) internal returns (bool) {
/* Insufficient allowance will be handled by the safe subtraction. */
tokenState.setAllowance(from, sender, tokenState.allowance(from, sender).sub(value));
return _internalTransfer(from, to, value);
}
/**
* @notice Approves spender to transfer on the message sender's behalf.
*/
function approve(address spender, uint value) public optionalProxy returns (bool) {
address sender = messageSender;
tokenState.setAllowance(sender, spender, value);
emitApproval(sender, spender, value);
return true;
}
/* ========== EVENTS ========== */
event Transfer(address indexed from, address indexed to, uint value);
bytes32 constant TRANSFER_SIG = keccak256("Transfer(address,address,uint256)");
function emitTransfer(address from, address to, uint value) internal {
proxy._emit(abi.encode(value), 3, TRANSFER_SIG, bytes32(from), bytes32(to), 0);
}
event Approval(address indexed owner, address indexed spender, uint value);
bytes32 constant APPROVAL_SIG = keccak256("Approval(address,address,uint256)");
function emitApproval(address owner, address spender, uint value) internal {
proxy._emit(abi.encode(value), 3, APPROVAL_SIG, bytes32(owner), bytes32(spender), 0);
}
event TokenStateUpdated(address newTokenState);
bytes32 constant TOKENSTATEUPDATED_SIG = keccak256("TokenStateUpdated(address)");
function emitTokenStateUpdated(address newTokenState) internal {
proxy._emit(abi.encode(newTokenState), 1, TOKENSTATEUPDATED_SIG, 0, 0, 0);
}
}
interface ISystemStatus {
function requireSystemActive() external view;
function requireIssuanceActive() external view;
function requireExchangeActive() external view;
function requireSynthActive(bytes32 currencyKey) external view;
function requireSynthsActive(bytes32 sourceCurrencyKey, bytes32 destinationCurrencyKey) external view;
}
/**
* @title FeePool Interface
* @notice Abstract contract to hold public getters
*/
contract IFeePool {
address public FEE_ADDRESS;
uint public exchangeFeeRate;
function amountReceivedFromExchange(uint value) external view returns (uint);
function amountReceivedFromTransfer(uint value) external view returns (uint);
function recordFeePaid(uint sUSDAmount) external;
function appendAccountIssuanceRecord(address account, uint lockedAmount, uint debtEntryIndex) external;
function setRewardsToDistribute(uint amount) external;
}
/**
* @title SynthetixState interface contract
* @notice Abstract contract to hold public getters
*/
contract ISynthetixState {
// A struct for handing values associated with an individual user's debt position
struct IssuanceData {
// Percentage of the total debt owned at the time
// of issuance. This number is modified by the global debt
// delta array. You can figure out a user's exit price and
// collateralisation ratio using a combination of their initial
// debt and the slice of global debt delta which applies to them.
uint initialDebtOwnership;
// This lets us know when (in relative terms) the user entered
// the debt pool so we can calculate their exit price and
// collateralistion ratio
uint debtEntryIndex;
}
uint[] public debtLedger;
uint public issuanceRatio;
mapping(address => IssuanceData) public issuanceData;
function debtLedgerLength() external view returns (uint);
function hasIssued(address account) external view returns (bool);
function incrementTotalIssuerCount() external;
function decrementTotalIssuerCount() external;
function setCurrentIssuanceData(address account, uint initialDebtOwnership) external;
function lastDebtLedgerEntry() external view returns (uint);
function appendDebtLedgerValue(uint value) external;
function clearIssuanceData(address account) external;
}
interface ISynth {
function burn(address account, uint amount) external;
function issue(address account, uint amount) external;
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function transferFromAndSettle(address from, address to, uint value) external returns (bool);
function balanceOf(address owner) external view returns (uint);
}
/**
* @title SynthetixEscrow interface
*/
interface ISynthetixEscrow {
function balanceOf(address account) public view returns (uint);
function appendVestingEntry(address account, uint quantity) public;
}
/**
* @title ExchangeRates interface
*/
interface IExchangeRates {
function effectiveValue(bytes32 sourceCurrencyKey, uint sourceAmount, bytes32 destinationCurrencyKey)
external
view
returns (uint);
function rateForCurrency(bytes32 currencyKey) external view returns (uint);
function ratesForCurrencies(bytes32[] currencyKeys) external view returns (uint[] memory);
function rateIsStale(bytes32 currencyKey) external view returns (bool);
function rateIsFrozen(bytes32 currencyKey) external view returns (bool);
function anyRateIsStale(bytes32[] currencyKeys) external view returns (bool);
function getCurrentRoundId(bytes32 currencyKey) external view returns (uint);
function effectiveValueAtRound(
bytes32 sourceCurrencyKey,
uint sourceAmount,
bytes32 destinationCurrencyKey,
uint roundIdForSrc,
uint roundIdForDest
) external view returns (uint);
function getLastRoundIdBeforeElapsedSecs(
bytes32 currencyKey,
uint startingRoundId,
uint startingTimestamp,
uint timediff
) external view returns (uint);
function ratesAndStaleForCurrencies(bytes32[] currencyKeys) external view returns (uint[], bool);
function rateAndTimestampAtRound(bytes32 currencyKey, uint roundId) external view returns (uint rate, uint time);
}
/**
* @title Synthetix interface contract
* @notice Abstract contract to hold public getters
* @dev pseudo interface, actually declared as contract to hold the public getters
*/
contract ISynthetix {
// ========== PUBLIC STATE VARIABLES ==========
uint public totalSupply;
mapping(bytes32 => Synth) public synths;
mapping(address => bytes32) public synthsByAddress;
// ========== PUBLIC FUNCTIONS ==========
function balanceOf(address account) public view returns (uint);
function transfer(address to, uint value) public returns (bool);
function transferFrom(address from, address to, uint value) public returns (bool);
function exchange(bytes32 sourceCurrencyKey, uint sourceAmount, bytes32 destinationCurrencyKey)
external
returns (uint amountReceived);
function issueSynths(uint amount) external;
function issueMaxSynths() external;
function burnSynths(uint amount) external;
function burnSynthsToTarget() external;
function settle(bytes32 currencyKey) external returns (uint reclaimed, uint refunded, uint numEntries);
function collateralisationRatio(address issuer) public view returns (uint);
function totalIssuedSynths(bytes32 currencyKey) public view returns (uint);
function totalIssuedSynthsExcludeEtherCollateral(bytes32 currencyKey) public view returns (uint);
function debtBalanceOf(address issuer, bytes32 currencyKey) public view returns (uint);
function debtBalanceOfAndTotalDebt(address issuer, bytes32 currencyKey)
public
view
returns (uint debtBalance, uint totalSystemValue);
function remainingIssuableSynths(address issuer)
public
view
returns (uint maxIssuable, uint alreadyIssued, uint totalSystemDebt);
function maxIssuableSynths(address issuer) public view returns (uint maxIssuable);
function isWaitingPeriod(bytes32 currencyKey) external view returns (bool);
function emitSynthExchange(
address account,
bytes32 fromCurrencyKey,
uint fromAmount,
bytes32 toCurrencyKey,
uint toAmount,
address toAddress
) external;
function emitExchangeReclaim(address account, bytes32 currencyKey, uint amount) external;
function emitExchangeRebate(address account, bytes32 currencyKey, uint amount) external;
}
interface IExchanger {
function maxSecsLeftInWaitingPeriod(address account, bytes32 currencyKey) external view returns (uint);
function feeRateForExchange(bytes32 sourceCurrencyKey, bytes32 destinationCurrencyKey) external view returns (uint);
function settlementOwing(address account, bytes32 currencyKey)
external
view
returns (uint reclaimAmount, uint rebateAmount, uint numEntries);
function settle(address from, bytes32 currencyKey) external returns (uint reclaimed, uint refunded, uint numEntries);
function exchange(
address from,
bytes32 sourceCurrencyKey,
uint sourceAmount,
bytes32 destinationCurrencyKey,
address destinationAddress
) external returns (uint amountReceived);
function exchangeOnBehalf(
address exchangeForAddress,
address from,
bytes32 sourceCurrencyKey,
uint sourceAmount,
bytes32 destinationCurrencyKey
) external returns (uint amountReceived);
function calculateAmountAfterSettlement(address from, bytes32 currencyKey, uint amount, uint refunded)
external
view
returns (uint amountAfterSettlement);
}
interface IIssuer {
function issueSynths(address from, uint amount) external;
function issueSynthsOnBehalf(address issueFor, address from, uint amount) external;
function issueMaxSynths(address from) external;
function issueMaxSynthsOnBehalf(address issueFor, address from) external;
function burnSynths(address from, uint amount) external;
function burnSynthsOnBehalf(address burnForAddress, address from, uint amount) external;
function burnSynthsToTarget(address from) external;
function burnSynthsToTargetOnBehalf(address burnForAddress, address from) external;
function canBurnSynths(address account) external view returns (bool);
function lastIssueEvent(address account) external view returns (uint);
}
// https://docs.synthetix.io/contracts/AddressResolver
contract AddressResolver is Owned {
mapping(bytes32 => address) public repository;
constructor(address _owner) public Owned(_owner) {}
/* ========== MUTATIVE FUNCTIONS ========== */
function importAddresses(bytes32[] names, address[] destinations) public onlyOwner {
require(names.length == destinations.length, "Input lengths must match");
for (uint i = 0; i < names.length; i++) {
repository[names[i]] = destinations[i];
}
}
/* ========== VIEWS ========== */
function getAddress(bytes32 name) public view returns (address) {
return repository[name];
}
function requireAndGetAddress(bytes32 name, string reason) public view returns (address) {
address _foundAddress = repository[name];
require(_foundAddress != address(0), reason);
return _foundAddress;
}
}
// https://docs.synthetix.io/contracts/MixinResolver
contract MixinResolver is Owned {
AddressResolver public resolver;
mapping(bytes32 => address) private addressCache;
bytes32[] public resolverAddressesRequired;
uint public constant MAX_ADDRESSES_FROM_RESOLVER = 24;
constructor(address _owner, address _resolver, bytes32[MAX_ADDRESSES_FROM_RESOLVER] _addressesToCache)
public
Owned(_owner)
{
for (uint i = 0; i < _addressesToCache.length; i++) {
if (_addressesToCache[i] != bytes32(0)) {
resolverAddressesRequired.push(_addressesToCache[i]);
} else {
// End early once an empty item is found - assumes there are no empty slots in
// _addressesToCache
break;
}
}
resolver = AddressResolver(_resolver);
// Do not sync the cache as addresses may not be in the resolver yet
}
/* ========== SETTERS ========== */
function setResolverAndSyncCache(AddressResolver _resolver) external onlyOwner {
resolver = _resolver;
for (uint i = 0; i < resolverAddressesRequired.length; i++) {
bytes32 name = resolverAddressesRequired[i];
// Note: can only be invoked once the resolver has all the targets needed added
addressCache[name] = resolver.requireAndGetAddress(name, "Resolver missing target");
}
}
/* ========== VIEWS ========== */
function requireAndGetAddress(bytes32 name, string reason) internal view returns (address) {
address _foundAddress = addressCache[name];
require(_foundAddress != address(0), reason);
return _foundAddress;
}
// Note: this could be made external in a utility contract if addressCache was made public
// (used for deployment)
function isResolverCached(AddressResolver _resolver) external view returns (bool) {
if (resolver != _resolver) {
return false;
}
// otherwise, check everything
for (uint i = 0; i < resolverAddressesRequired.length; i++) {
bytes32 name = resolverAddressesRequired[i];
// false if our cache is invalid or if the resolver doesn't have the required address
if (resolver.getAddress(name) != addressCache[name] || addressCache[name] == address(0)) {
return false;
}
}
return true;
}
// Note: can be made external into a utility contract (used for deployment)
function getResolverAddressesRequired() external view returns (bytes32[MAX_ADDRESSES_FROM_RESOLVER] addressesRequired) {
for (uint i = 0; i < resolverAddressesRequired.length; i++) {
addressesRequired[i] = resolverAddressesRequired[i];
}
}
/* ========== INTERNAL FUNCTIONS ========== */
function appendToAddressCache(bytes32 name) internal {
resolverAddressesRequired.push(name);
require(resolverAddressesRequired.length < MAX_ADDRESSES_FROM_RESOLVER, "Max resolver cache size met");
// Because this is designed to be called internally in constructors, we don't
// check the address exists already in the resolver
addressCache[name] = resolver.getAddress(name);
}
}
// https://docs.synthetix.io/contracts/Synth
contract Synth is ExternStateToken, MixinResolver {
/* ========== STATE VARIABLES ========== */
// Currency key which identifies this Synth to the Synthetix system
bytes32 public currencyKey;
uint8 public constant DECIMALS = 18;
// Where fees are pooled in sUSD
address public constant FEE_ADDRESS = 0xfeEFEEfeefEeFeefEEFEEfEeFeefEEFeeFEEFEeF;
/* ========== ADDRESS RESOLVER CONFIGURATION ========== */
bytes32 private constant CONTRACT_SYSTEMSTATUS = "SystemStatus";
bytes32 private constant CONTRACT_SYNTHETIX = "Synthetix";
bytes32 private constant CONTRACT_EXCHANGER = "Exchanger";
bytes32 private constant CONTRACT_ISSUER = "Issuer";
bytes32 private constant CONTRACT_FEEPOOL = "FeePool";
bytes32[24] internal addressesToCache = [
CONTRACT_SYSTEMSTATUS,
CONTRACT_SYNTHETIX,
CONTRACT_EXCHANGER,
CONTRACT_ISSUER,
CONTRACT_FEEPOOL
];
/* ========== CONSTRUCTOR ========== */
constructor(
address _proxy,
TokenState _tokenState,
string _tokenName,
string _tokenSymbol,
address _owner,
bytes32 _currencyKey,
uint _totalSupply,
address _resolver
)
public
ExternStateToken(_proxy, _tokenState, _tokenName, _tokenSymbol, _totalSupply, DECIMALS, _owner)
MixinResolver(_owner, _resolver, addressesToCache)
{
require(_proxy != address(0), "_proxy cannot be 0");
require(_owner != 0, "_owner cannot be 0");
currencyKey = _currencyKey;
}
/* ========== MUTATIVE FUNCTIONS ========== */
function transfer(address to, uint value) public optionalProxy returns (bool) {
_ensureCanTransfer(messageSender, value);
// transfers to FEE_ADDRESS will be exchanged into sUSD and recorded as fee
if (to == FEE_ADDRESS) {
return _transferToFeeAddress(to, value);
}
// transfers to 0x address will be burned
if (to == address(0)) {
return _internalBurn(messageSender, value);
}
return super._internalTransfer(messageSender, to, value);
}
function transferAndSettle(address to, uint value) public optionalProxy returns (bool) {
systemStatus().requireSynthActive(currencyKey);
(, , uint numEntriesSettled) = exchanger().settle(messageSender, currencyKey);
// Save gas instead of calling transferableSynths
uint balanceAfter = value;
if (numEntriesSettled > 0) {
balanceAfter = tokenState.balanceOf(messageSender);
}
// Reduce the value to transfer if balance is insufficient after reclaimed
value = value > balanceAfter ? balanceAfter : value;
return super._internalTransfer(messageSender, to, value);
}
function transferFrom(address from, address to, uint value) public optionalProxy returns (bool) {
_ensureCanTransfer(from, value);
return _internalTransferFrom(from, to, value);
}
function transferFromAndSettle(address from, address to, uint value) public optionalProxy returns (bool) {
systemStatus().requireSynthActive(currencyKey);
(, , uint numEntriesSettled) = exchanger().settle(from, currencyKey);
// Save gas instead of calling transferableSynths
uint balanceAfter = value;
if (numEntriesSettled > 0) {
balanceAfter = tokenState.balanceOf(from);
}
// Reduce the value to transfer if balance is insufficient after reclaimed
value = value >= balanceAfter ? balanceAfter : value;
return _internalTransferFrom(from, to, value);
}
/**
* @notice _transferToFeeAddress function
* non-sUSD synths are exchanged into sUSD via synthInitiatedExchange
* notify feePool to record amount as fee paid to feePool */
function _transferToFeeAddress(address to, uint value) internal returns (bool) {
uint amountInUSD;
// sUSD can be transferred to FEE_ADDRESS directly
if (currencyKey == "sUSD") {
amountInUSD = value;
super._internalTransfer(messageSender, to, value);
} else {
// else exchange synth into sUSD and send to FEE_ADDRESS
amountInUSD = exchanger().exchange(messageSender, currencyKey, value, "sUSD", FEE_ADDRESS);
}
// Notify feePool to record sUSD to distribute as fees
feePool().recordFeePaid(amountInUSD);
return true;
}
// Allow synthetix to issue a certain number of synths from an account.
// forward call to _internalIssue
function issue(address account, uint amount) external onlyInternalContracts {
_internalIssue(account, amount);
}
// Allow synthetix or another synth contract to burn a certain number of synths from an account.
// forward call to _internalBurn
function burn(address account, uint amount) external onlyInternalContracts {
_internalBurn(account, amount);
}
function _internalIssue(address account, uint amount) internal {
tokenState.setBalanceOf(account, tokenState.balanceOf(account).add(amount));
totalSupply = totalSupply.add(amount);
emitTransfer(address(0), account, amount);
emitIssued(account, amount);
}
function _internalBurn(address account, uint amount) internal returns (bool) {
tokenState.setBalanceOf(account, tokenState.balanceOf(account).sub(amount));
totalSupply = totalSupply.sub(amount);
emitTransfer(account, address(0), amount);
emitBurned(account, amount);
return true;
}
// Allow owner to set the total supply on import.
function setTotalSupply(uint amount) external optionalProxy_onlyOwner {
totalSupply = amount;
}
/* ========== VIEWS ========== */
function systemStatus() internal view returns (ISystemStatus) {
return ISystemStatus(requireAndGetAddress(CONTRACT_SYSTEMSTATUS, "Missing SystemStatus address"));
}
function synthetix() internal view returns (ISynthetix) {
return ISynthetix(requireAndGetAddress(CONTRACT_SYNTHETIX, "Missing Synthetix address"));
}
function feePool() internal view returns (IFeePool) {
return IFeePool(requireAndGetAddress(CONTRACT_FEEPOOL, "Missing FeePool address"));
}
function exchanger() internal view returns (IExchanger) {
return IExchanger(requireAndGetAddress(CONTRACT_EXCHANGER, "Missing Exchanger address"));
}
function issuer() internal view returns (IIssuer) {
return IIssuer(requireAndGetAddress(CONTRACT_ISSUER, "Missing Issuer address"));
}
function _ensureCanTransfer(address from, uint value) internal view {
require(exchanger().maxSecsLeftInWaitingPeriod(from, currencyKey) == 0, "Cannot transfer during waiting period");
require(transferableSynths(from) >= value, "Insufficient balance after any settlement owing");
systemStatus().requireSynthActive(currencyKey);
}
function transferableSynths(address account) public view returns (uint) {
(uint reclaimAmount, , ) = exchanger().settlementOwing(account, currencyKey);
// Note: ignoring rebate amount here because a settle() is required in order to
// allow the transfer to actually work
uint balance = tokenState.balanceOf(account);
if (reclaimAmount > balance) {
return 0;
} else {
return balance.sub(reclaimAmount);
}
}
/* ========== INTERNAL FUNCTIONS ========== */
function _internalTransferFrom(address from, address to, uint value) internal returns (bool) {
// Skip allowance update in case of infinite allowance
if (tokenState.allowance(from, messageSender) != uint(-1)) {
// Reduce the allowance by the amount we're transferring.
// The safeSub call will handle an insufficient allowance.
tokenState.setAllowance(from, messageSender, tokenState.allowance(from, messageSender).sub(value));
}
return super._internalTransfer(from, to, value);
}
/* ========== MODIFIERS ========== */
modifier onlyInternalContracts() {
bool isSynthetix = msg.sender == address(synthetix());
bool isFeePool = msg.sender == address(feePool());
bool isExchanger = msg.sender == address(exchanger());
bool isIssuer = msg.sender == address(issuer());
require(
isSynthetix || isFeePool || isExchanger || isIssuer,
"Only Synthetix, FeePool, Exchanger or Issuer contracts allowed"
);
_;
}
/* ========== EVENTS ========== */
event Issued(address indexed account, uint value);
bytes32 private constant ISSUED_SIG = keccak256("Issued(address,uint256)");
function emitIssued(address account, uint value) internal {
proxy._emit(abi.encode(value), 2, ISSUED_SIG, bytes32(account), 0, 0);
}
event Burned(address indexed account, uint value);
bytes32 private constant BURNED_SIG = keccak256("Burned(address,uint256)");
function emitBurned(address account, uint value) internal {
proxy._emit(abi.encode(value), 2, BURNED_SIG, bytes32(account), 0, 0);
}
}