RewardEscrow¶
Description¶
This is the mechanism for distributing SNX rewards from the inflationary supply. When an SNX staker claims fees, the inflationary reward component is escrowed in this contract and an entry is added to an escrow schedule for that staker for them to claim after a year. These vesting schedules can only be appended to by the FeePool contract.
The logic of RewardEscrow is derived from the SynthetixEscrow contract.
Source: contracts/RewardEscrow.sol
Architecture¶
Related Contracts¶
Variables¶
MAX_VESTING_ENTRIES¶
This constant limits vesting schedules to be shorter than 260 entries long so that iteration is bounded. This allows up to five years of vesting entries to be handled, if one is generated per weekly fee period.
Value: 52 * 5
Type: uint256
feePool¶
The address of the FeePool contract.
Type: contract IFeePool
synthetix¶
The address of the main Synthetix contract.
Type: contract ISynthetix
totalEscrowedAccountBalance¶
The quantity of remaining tokens for each account; it saves the recomputation involved in summing over vestingSchedules entries.
Type: mapping(address => uint256)
totalEscrowedBalance¶
A record of the total remaining vested balance in this contract, which should be equal to the actual SNX balance.
Type: uint256
totalVestedAccountBalance¶
The quantity of tokens that have already been vested for each account.
Type: mapping(address => uint256)
vestingSchedules¶
Stores the vesting schedule for each for each account. Each schedule is a list of (vesting timestamp, quantity) pairs in ascending time order.
Type: mapping(address => uint256[2][])
Constructor¶
constructor¶
Initialises the Synthetix and FeePool contract addresses, and the inherited Owned instance.
Details
Signature
constructor(address _owner, contract ISynthetix _synthetix, contract IFeePool _feePool)
Visibility
public
State Mutability
``
Views¶
balanceOf¶
An alias to totalEscrowedAccountBalance[account] for ERC20 integration.
Details
Signature
balanceOf(address account) view returns (uint256)
Visibility
public
State Mutability
view
checkAccountSchedule¶
Returns the full vesting schedule for a given account.
Details
Signature
checkAccountSchedule(address account) view returns (uint256[520])
Visibility
public
State Mutability
view
getNextVestingEntry¶
Returns the next vesting entry in the same manner as getNextVestingIndex. Returns [0,0] if there is no next vesting entry.
Details
Signature
getNextVestingEntry(address account) view returns (uint256[2])
Visibility
public
State Mutability
view
getNextVestingIndex¶
Returns the index of the next vesting entry that will vest for a given account. Returns one past the end if there are none remaining.
The function iterates until it finds the first nonzero vesting entry timestamp, so the gas cost increases slightly as more entries vest. A full schedule of 260 entries would cost a little over 50\,000 gas to iterate over.
Details
Signature
getNextVestingIndex(address account) view returns (uint256)
Visibility
public
State Mutability
view
getNextVestingQuantity¶
Returns the SNX quantity of the next vesting entry. Returns 0 if there is no such entry.
Details
Signature
getNextVestingQuantity(address account) view returns (uint256)
Visibility
external
State Mutability
view
getNextVestingTime¶
Returns the timestamp of the next vesting entry. Returns 0 if there is no such entry.
Details
Signature
getNextVestingTime(address account) view returns (uint256)
Visibility
external
State Mutability
view
getVestingQuantity¶
Returns the quantity of SNX a given schedule entry will yield.
Details
Signature
getVestingQuantity(address account, uint256 index) view returns (uint256)
Visibility
public
State Mutability
view
getVestingScheduleEntry¶
Returns a particular schedule entry for an account, which is a pair of uints: (vesting timestamp, SNX quantity).
This is here because the public function generated for vestingSchedules awkwardly requires the index into the pair as its third argument.
Details
Signature
getVestingScheduleEntry(address account, uint256 index) view returns (uint256[2])
Visibility
public
State Mutability
view
getVestingTime¶
Returns the time at which a given schedule entry will vest.
Details
Signature
getVestingTime(address account, uint256 index) view returns (uint256)
Visibility
public
State Mutability
view
numVestingEntries¶
The number of entries in an account's vesting schedule, including those already claimed.
Details
Signature
numVestingEntries(address account) view returns (uint256)
Visibility
external
State Mutability
view
Restricted Functions¶
appendVestingEntry¶
This function allows the FeePool contract to add a new entry to a given account's vesting schedule when it claims its fees. All new entries are set to vest after one year.
Details
Signature
appendVestingEntry(address account, uint256 quantity)
Visibility
external
State Mutability
``
Modifiers
setFeePool¶
Sets the address of the FeePool contract, so that new vesting entries can be generated.
Details
Signature
setFeePool(contract IFeePool _feePool)
Visibility
external
State Mutability
``
Modifiers
Emits
setSynthetix¶
Sets the address of the Synthetix contract, so that escrowed SNX can be transferred to accounts claiming them.
Details
Signature
setSynthetix(contract ISynthetix _synthetix)
Visibility
external
State Mutability
``
Modifiers
Emits
Internal Functions¶
_appendVestingEntry¶
Details
Signature
_appendVestingEntry(address account, uint256 quantity)
Visibility
internal
State Mutability
``
Requires
Emits
_numVestingEntries¶
Details
Signature
_numVestingEntries(address account) view returns (uint256)
Visibility
internal
State Mutability
view
External Functions¶
vest¶
Finds all vesting schedule entries that have come due for the caller and transfers the total quantity of tokens to them. Vested entries are overwritten with [0,0].
Details
Signature
vest()
Visibility
external
State Mutability
``
Modifiers¶
onlyFeePool¶
Reverts the transaction if the msg.sender is not the FeePool.
Events¶
FeePoolUpdated¶
Records that the fee pool contract address was altered.
Signature: FeePoolUpdated(address newFeePool)
SynthetixUpdated¶
Records that the SNX contract address was altered.
Signature: SynthetixUpdated(address newSynthetix)
Vested¶
Records that an account vested a quantity of tokens.
Signature: Vested(address beneficiary, uint256 time, uint256 value)
VestingEntryCreated¶
Records that the fee pool created a vesting entry.
Signature: VestingEntryCreated(address beneficiary, uint256 time, uint256 value)