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Bump eth-erc20. add initial single and cap contract adaptations

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This commit is contained in:
nolash 2021-06-05 07:50:59 +02:00
parent 3c871e5758
commit 093fcbccd5
Signed by: lash
GPG Key ID: 21D2E7BB88C2A746
14 changed files with 1376 additions and 41 deletions
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0
python/erc20_demurrage_token/data/DemurrageTokenMultiCap.bin Normal file
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python/erc20_demurrage_token/data/DemurrageTokenMultiCap.json Normal file
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2
python/erc20_demurrage_token/data/DemurrageTokenMultiNocap.bin
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python/erc20_demurrage_token/data/DemurrageTokenSingleNocap.bin Normal file
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python/erc20_demurrage_token/data/DemurrageTokenSingleNocap.json Normal file
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49
python/erc20_demurrage_token/token.py
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@ -40,13 +40,13 @@ class DemurrageTokenSettings:
class DemurrageToken(ERC20):
__abi = None
__bytecode = None
__abi = {}
__bytecode = {}
def constructor(self, sender_address, settings, redistribute=True, cap=0, tx_format=TxFormat.JSONRPC):
if not redistribute or cap:
raise NotImplementedError('token cap and sink only redistribution not yet implemented')
code = DemurrageToken.bytecode()
if int(cap) < 0:
raise ValueError('cap must be 0 or positive integer')
code = DemurrageToken.bytecode(multi=redistribute, cap=cap>0)
enc = ABIContractEncoder()
enc.string(settings.name)
enc.string(settings.symbol)
@ -64,22 +64,39 @@ class DemurrageToken(ERC20):
def gas(code=None):
return 3500000
@staticmethod
def abi():
if DemurrageToken.__abi == None:
f = open(os.path.join(data_dir, 'DemurrageTokenMultiNocap.json'), 'r')
DemurrageToken.__abi = json.load(f)
f.close()
return DemurrageToken.__abi
def __to_contract_name(multi, cap):
name = 'DemurrageToken'
if multi:
name += 'Multi'
else:
name += 'Single'
if cap:
name += 'Cap'
else:
name += 'Nocap'
return name
@staticmethod
def bytecode():
if DemurrageToken.__bytecode == None:
f = open(os.path.join(data_dir, 'DemurrageTokenMultiNocap.bin'), 'r')
DemurrageToken.__bytecode = f.read()
def abi(multi=True, cap=False):
name = DemurrageToken.__to_contract_name(multi, cap)
if DemurrageToken.__abi.get(name) == None:
f = open(os.path.join(data_dir, name + '.json'), 'r')
DemurrageToken.__abi[name] = json.load(f)
f.close()
return DemurrageToken.__bytecode
return DemurrageToken.__abi[name]
@staticmethod
def bytecode(multi=True, cap=False):
name = DemurrageToken.__to_contract_name(multi, cap)
if DemurrageToken.__bytecode.get(name) == None:
f = open(os.path.join(data_dir, name + '.bin'), 'r')
DemurrageToken.__bytecode[name] = f.read()
f.close()
return DemurrageToken.__bytecode[name]
def add_minter(self, contract_address, sender_address, address, tx_format=TxFormat.JSONRPC):

2
python/requirements.txt
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@ -1,3 +1,3 @@
chainlib~=0.0.3rc3
eth-erc20~=0.0.9a3
eth-erc20~=0.0.9a4
crypto-dev-signer~=0.4.14b3

33
python/tests/base.py
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@ -35,6 +35,10 @@ class TestDemurrage(EthTesterCase):
def setUp(self):
super(TestDemurrage, self).setUp()
self.tax_level = TAX_LEVEL
self.period = PERIOD
nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
self.settings = DemurrageTokenSettings()
self.settings.name = 'Foo Token'
@ -64,16 +68,31 @@ class TestDemurrage(EthTesterCase):
class TestDemurrageDefault(TestDemurrage):
def __deploy(self, interface):
self.default_supply = 1000000000000
self.supply_cap = self.default_supply * 10
(tx_hash, o) = interface.constructor(self.accounts[0], self.settings, redistribute=True, cap=0)
r = self.rpc.do(o)
o = receipt(tx_hash)
r = self.rpc.do(o)
self.assertEqual(r['status'], 1)
self.addresses['MultiNocap'] = r['contract_address']
(tx_hash, o) = interface.constructor(self.accounts[0], self.settings, redistribute=False, cap=0)
r = self.rpc.do(o)
o = receipt(tx_hash)
r = self.rpc.do(o)
self.assertEqual(r['status'], 1)
self.addresses['SingleNocap'] = r['contract_address']
def setUp(self):
super(TestDemurrageDefault, self).setUp()
nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
(tx_hash, o) = c.constructor(self.accounts[0], self.settings)
r = self.rpc.do(o)
o = receipt(tx_hash)
r = self.rpc.do(o)
self.assertEqual(r['status'], 1)
self.address = r['contract_address']
self.addresses = {}
self.__deploy(c)
self.address = self.addresses['MultiNocap']

21
python/tests/test_redistribution.py
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@ -26,11 +26,6 @@ logg = logging.getLogger()
testdir = os.path.dirname(__file__)
#BLOCKTIME = 5 # seconds
TAX_LEVEL = 10000 * 2 # 2%
#PERIOD = int(60/BLOCKTIME) * 60 * 24 * 30 # month
PERIOD = 1
class TestRedistribution(TestDemurrageDefault):
@ -104,7 +99,7 @@ class TestRedistribution(TestDemurrageDefault):
def test_redistribution_balance_on_zero_participants(self):
supply = 1000000000000
supply = self.default_supply
nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
@ -127,7 +122,7 @@ class TestRedistribution(TestDemurrageDefault):
o = c.total_supply(self.address, sender_address=self.accounts[0])
r = self.rpc.do(o)
total_supply = c.parse_total_supply(r)
sink_increment = int(total_supply * (TAX_LEVEL / 1000000))
sink_increment = int(total_supply * (self.tax_level / 1000000))
self.assertEqual(supply, total_supply)
for l in rcpt['logs']:
@ -136,14 +131,14 @@ class TestRedistribution(TestDemurrageDefault):
self.assertEqual(period, 2)
b = bytes.fromhex(strip_0x(l['data']))
remainder = int.from_bytes(b, 'big')
self.assertEqual(remainder, int((1000000 - TAX_LEVEL) * (10 ** 32)))
self.assertEqual(remainder, int((1000000 - self.tax_level) * (10 ** 32)))
o = c.balance_of(self.address, self.sink_address, sender_address=self.accounts[0])
r = self.rpc.do(o)
sink_balance = c.parse_balance_of(r)
self.assertEqual(sink_balance, int(sink_increment * 0.98))
self.assertEqual(sink_balance, int(sink_increment * (1000000 - TAX_LEVEL) / 1000000))
self.assertEqual(sink_balance, int(sink_increment * (1000000 - self.tax_level) / 1000000))
o = c.balance_of(self.address, self.accounts[1], sender_address=self.accounts[0])
r = self.rpc.do(o)
@ -215,14 +210,14 @@ class TestRedistribution(TestDemurrageDefault):
r = self.rpc.do(o)
bummer_balance = c.parse_balance_of(r)
self.assertEqual(bummer_balance, mint_amount - (mint_amount * (TAX_LEVEL / 1000000)))
self.assertEqual(bummer_balance, mint_amount - (mint_amount * (self.tax_level / 1000000)))
logg.debug('bal {} '.format(bummer_balance))
o = c.balance_of(self.address, self.accounts[1], sender_address=self.accounts[0])
r = self.rpc.do(o)
bummer_balance = c.parse_balance_of(r)
spender_balance = mint_amount - spend_amount
spender_decayed_balance = int(spender_balance - (spender_balance * (TAX_LEVEL / 1000000)))
spender_decayed_balance = int(spender_balance - (spender_balance * (self.tax_level / 1000000)))
self.assertEqual(bummer_balance, spender_decayed_balance)
logg.debug('bal {} '.format(bummer_balance))
@ -254,9 +249,9 @@ class TestRedistribution(TestDemurrageDefault):
actual_period = c.parse_actual_period(r)
logg.debug('period {}'.format(actual_period))
redistribution = int((z / 2) * (TAX_LEVEL / 1000000))
redistribution = int((z / 2) * (self.tax_level / 1000000))
spender_new_base_balance = ((mint_amount - spend_amount) + redistribution)
spender_new_decayed_balance = int(spender_new_base_balance - (spender_new_base_balance * (TAX_LEVEL / 1000000)))
spender_new_decayed_balance = int(spender_new_base_balance - (spender_new_base_balance * (self.tax_level / 1000000)))
o = c.balance_of(self.address, self.accounts[1], sender_address=self.accounts[0])
r = self.rpc.do(o)

61
python/tests/test_single.py Normal file
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@ -0,0 +1,61 @@
import os
import unittest
import json
import logging
# external imports
from chainlib.eth.constant import ZERO_ADDRESS
from chainlib.eth.nonce import RPCNonceOracle
from chainlib.eth.tx import receipt
from chainlib.eth.block import block_latest
from chainlib.eth.address import to_checksum_address
from hexathon import (
strip_0x,
add_0x,
)
# local imports
from erc20_demurrage_token import DemurrageToken
# test imports
from tests.base import TestDemurrageDefault
logging.basicConfig(level=logging.DEBUG)
logg = logging.getLogger()
testdir = os.path.dirname(__file__)
class TestRedistributionSingle(TestDemurrageDefault):
def test_single_even_if_multiple(self):
nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
(tx_hash, o) = c.mint_to(self.address, self.accounts[0], self.accounts[1], 100000000)
r = self.rpc.do(o)
external_address = to_checksum_address('0x' + os.urandom(20).hex())
nonce_oracle = RPCNonceOracle(self.accounts[2], self.rpc)
c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
(tx_hash, o) = c.transfer(self.address, self.accounts[1], external_address, 10000000)
r = self.rpc.do(o)
nonce_oracle = RPCNonceOracle(self.accounts[3], self.rpc)
c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
(tx_hash, o) = c.transfer(self.address, self.accounts[2], external_address, 20000000)
r = self.rpc.do(o)
self.backend.time_travel(self.start_time + 61)
(tx_hash, o) = c.apply_demurrage(self.address, self.accounts[0])
self.rpc.do(o)
o = receipt(tx_hash)
rcpt = self.rpc.do(o)
self.assertEqual(rcpt['status'], 1)
(tx_hash, o) = c.change_period(self.address, self.accounts[0])
self.rpc.do(o)
o = receipt(tx_hash)
r = self.rpc.do(o)
self.assertEqual(r['status'], 1)

616
solidity/DemurrageTokenMultiCap.sol Normal file
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@ -0,0 +1,616 @@
pragma solidity > 0.6.11;
// SPDX-License-Identifier: GPL-3.0-or-later
contract DemurrageTokenMultiCap {
// Redistribution bit field, with associated shifts and masks
// (Uses sub-byte boundaries)
bytes32[] public redistributions; // uint1(isFractional) | uint95(unused) | uint20(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
uint8 constant shiftRedistributionPeriod = 0;
uint256 constant maskRedistributionPeriod = 0x00000000000000000000000000000000000000000000000000000000ffffffff; // (1 << 32) - 1
uint8 constant shiftRedistributionValue = 32;
uint256 constant maskRedistributionValue = 0x00000000000000000000000000000000000000ffffffffffffffffff00000000; // ((1 << 72) - 1) << 32
uint8 constant shiftRedistributionParticipants = 104;
uint256 constant maskRedistributionParticipants = 0x00000000000000000000000000000fffffffff00000000000000000000000000; // ((1 << 36) - 1) << 104
uint8 constant shiftRedistributionDemurrage = 140;
uint256 constant maskRedistributionDemurrage = 0x000000000000000000000000fffff00000000000000000000000000000000000; // ((1 << 20) - 1) << 140
uint8 constant shiftRedistributionIsFractional = 255;
uint256 constant maskRedistributionIsFractional = 0x8000000000000000000000000000000000000000000000000000000000000000; // 1 << 255
// Account bit field, with associated shifts and masks
// Mirrors structure of redistributions for consistency
mapping (address => bytes32) account; // uint152(unused) | uint32(period) | uint72(value)
uint8 constant shiftAccountValue = 0;
uint256 constant maskAccountValue = 0x0000000000000000000000000000000000000000000000ffffffffffffffffff; // (1 << 72) - 1
uint8 constant shiftAccountPeriod = 72;
uint256 constant maskAccountPeriod = 0x00000000000000000000000000000000000000ffffffff000000000000000000; // ((1 << 32) - 1) << 72
// Cached demurrage amount, ppm with 38 digit resolution
uint128 public demurrageAmount;
// Cached demurrage period; the period for which demurrageAmount was calculated
uint128 public demurragePeriod;
// Implements EIP172
address public owner;
address newOwner;
// Implements ERC20
string public name;
// Implements ERC20
string public symbol;
// Implements ERC20
uint256 public decimals;
// Implements ERC20
uint256 public totalSupply;
// Maximum amount of tokens that can be minted
uint256 public supplyCap;
// Minimum amount of (demurraged) tokens an account must spend to participate in redistribution for a particular period
uint256 public minimumParticipantSpend;
// 128 bit resolution of the demurrage divisor
// (this constant x 1000000 is contained within 128 bits)
uint256 constant ppmDivider = 100000000000000000000000000000000;
// Timestamp of start of periods (time which contract constructor was called)
uint256 public immutable periodStart;
// Duration of a single redistribution period in seconds
uint256 public immutable periodDuration;
// Demurrage in ppm per minute
uint256 public immutable taxLevel;
// Addresses allowed to mint new tokens
mapping (address => bool) minter;
// Storage for ERC20 approve/transferFrom methods
mapping (address => mapping (address => uint256 ) ) allowance; // holder -> spender -> amount (amount is subject to demurrage)
// Address to send unallocated redistribution tokens
address sinkAddress;
// Implements ERC20
event Transfer(address indexed _from, address indexed _to, uint256 _value);
// Implements ERC20
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
// New tokens minted
event Mint(address indexed _minter, address indexed _beneficiary, uint256 _value);
// New demurrage cache milestone calculated
event Decayed(uint256 indexed _period, uint256 indexed _periodCount, uint256 indexed _oldAmount, uint256 _newAmount);
// When a new period threshold has been crossed
event Period(uint256 _period);
// Redistribution applied on a single eligible account
event Redistribution(address indexed _account, uint256 indexed _period, uint256 _value);
// Temporary event used in development, will be removed on prod
event Debug(bytes32 _foo);
// EIP173
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); // EIP173
constructor(string memory _name, string memory _symbol, uint8 _decimals, uint256 _taxLevelMinute, uint256 _periodMinutes, address _defaultSinkAddress uint256 _supplyCap) public {
// ACL setup
owner = msg.sender;
minter[owner] = true;
// ERC20 setup
name = _name;
symbol = _symbol;
decimals = _decimals;
// Demurrage setup
periodStart = block.timestamp;
periodDuration = _periodMinutes * 60;
demurrageAmount = uint128(ppmDivider * 1000000); // Represents 38 decimal places
demurragePeriod = 1;
taxLevel = _taxLevelMinute; // Represents 38 decimal places
bytes32 initialRedistribution = toRedistribution(0, 1000000, 0, 1);
redistributions.push(initialRedistribution);
// Misc settings
supplyCap = supplyCap;
sinkAddress = _defaultSinkAddress;
minimumParticipantSpend = 10 ** uint256(_decimals);
}
// Given address will be allowed to call the mintTo() function
function addMinter(address _minter) public returns (bool) {
require(msg.sender == owner);
minter[_minter] = true;
return true;
}
// Given address will no longer be allowed to call the mintTo() function
function removeMinter(address _minter) public returns (bool) {
require(msg.sender == owner || _minter == msg.sender);
minter[_minter] = false;
return true;
}
/// Implements ERC20
function balanceOf(address _account) public view returns (uint256) {
uint256 baseBalance;
uint256 currentDemurragedAmount;
uint256 periodCount;
baseBalance = baseBalanceOf(_account);
periodCount = actualPeriod() - demurragePeriod;
currentDemurragedAmount = uint128(decayBy(demurrageAmount, periodCount));
return (baseBalance * currentDemurragedAmount) / (ppmDivider * 1000000);
}
/// Balance unmodified by demurrage
function baseBalanceOf(address _account) public view returns (uint256) {
return uint256(account[_account]) & maskAccountValue;
}
/// Increases base balance for a single account
function increaseBaseBalance(address _account, uint256 _delta) private returns (bool) {
uint256 oldBalance;
uint256 newBalance;
uint256 workAccount;
workAccount = uint256(account[_account]);
if (_delta == 0) {
return false;
}
oldBalance = baseBalanceOf(_account);
newBalance = oldBalance + _delta;
require(uint160(newBalance) > uint160(oldBalance), 'ERR_WOULDWRAP'); // revert if increase would result in a wrapped value
workAccount &= (~maskAccountValue);
workAccount |= (newBalance & maskAccountValue);
account[_account] = bytes32(workAccount);
return true;
}
/// Decreases base balance for a single account
function decreaseBaseBalance(address _account, uint256 _delta) private returns (bool) {
uint256 oldBalance;
uint256 newBalance;
uint256 workAccount;
workAccount = uint256(account[_account]);
if (_delta == 0) {
return false;
}
oldBalance = baseBalanceOf(_account);
require(oldBalance >= _delta, 'ERR_OVERSPEND'); // overspend guard
newBalance = oldBalance - _delta;
workAccount &= (~maskAccountValue);
workAccount |= (newBalance & maskAccountValue);
account[_account] = bytes32(workAccount);
return true;
}
// Creates new tokens out of thin air, and allocates them to the given address
// Triggers tax
function mintTo(address _beneficiary, uint256 _amount) external returns (bool) {
uint256 baseAmount;
require(minter[msg.sender]);
require(_amount + totalSupply <= supplyCap);
changePeriod();
baseAmount = _amount;
totalSupply += _amount;
increaseBaseBalance(_beneficiary, baseAmount);
emit Mint(msg.sender, _beneficiary, _amount);
saveRedistributionSupply();
return true;
}
// Deserializes the redistribution word
// uint1(isFractional) | uint95(unused) | uint20(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
function toRedistribution(uint256 _participants, uint256 _demurrageModifierPpm, uint256 _value, uint256 _period) private pure returns(bytes32) {
bytes32 redistribution;
redistribution |= bytes32((_demurrageModifierPpm << shiftRedistributionDemurrage) & maskRedistributionDemurrage);
redistribution |= bytes32((_participants << shiftRedistributionParticipants) & maskRedistributionParticipants);
redistribution |= bytes32((_value << shiftRedistributionValue) & maskRedistributionValue);
redistribution |= bytes32(_period & maskRedistributionPeriod);
return redistribution;
}
// Serializes the demurrage period part of the redistribution word
function toRedistributionPeriod(bytes32 redistribution) public pure returns (uint256) {
return uint256(redistribution) & maskRedistributionPeriod;
}
// Serializes the supply part of the redistribution word
function toRedistributionSupply(bytes32 redistribution) public pure returns (uint256) {
return (uint256(redistribution) & maskRedistributionValue) >> shiftRedistributionValue;
}
// Serializes the number of participants part of the redistribution word
function toRedistributionParticipants(bytes32 redistribution) public pure returns (uint256) {
return (uint256(redistribution) & maskRedistributionParticipants) >> shiftRedistributionParticipants;
}
// Serializes the number of participants part of the redistribution word
function toRedistributionDemurrageModifier(bytes32 redistribution) public pure returns (uint256) {
return (uint256(redistribution) & maskRedistributionDemurrage) >> shiftRedistributionDemurrage;
}
// Client accessor to the redistributions array length
function redistributionCount() public view returns (uint256) {
return redistributions.length;
}
// Add number of participants for the current redistribution period by one
function incrementRedistributionParticipants() private returns (bool) {
bytes32 currentRedistribution;
uint256 tmpRedistribution;
uint256 participants;
currentRedistribution = redistributions[redistributions.length-1];
participants = toRedistributionParticipants(currentRedistribution) + 1;
tmpRedistribution = uint256(currentRedistribution);
tmpRedistribution &= (~maskRedistributionParticipants);
tmpRedistribution |= ((participants << shiftRedistributionParticipants) & maskRedistributionParticipants);
redistributions[redistributions.length-1] = bytes32(tmpRedistribution);
return true;
}
// Save the current total supply amount to the current redistribution period
function saveRedistributionSupply() private returns (bool) {
uint256 currentRedistribution;
currentRedistribution = uint256(redistributions[redistributions.length-1]);
currentRedistribution &= (~maskRedistributionValue);
currentRedistribution |= (totalSupply << shiftRedistributionValue);
redistributions[redistributions.length-1] = bytes32(currentRedistribution);
return true;
}
// Get the demurrage period of the current block number
function actualPeriod() public view returns (uint128) {
return uint128((block.timestamp - periodStart) / periodDuration + 1);
}
// Add an entered demurrage period to the redistribution array
function checkPeriod() private view returns (bytes32) {
bytes32 lastRedistribution;
uint256 currentPeriod;
lastRedistribution = redistributions[redistributions.length-1];
currentPeriod = this.actualPeriod();
if (currentPeriod <= toRedistributionPeriod(lastRedistribution)) {
return bytes32(0x00);
}
return lastRedistribution;
}
// Deserialize the pemurrage period for the given account is participating in
function accountPeriod(address _account) public view returns (uint256) {
return (uint256(account[_account]) & maskAccountPeriod) >> shiftAccountPeriod;
}
// Save the given demurrage period as the currently participation period for the given address
function registerAccountPeriod(address _account, uint256 _period) private returns (bool) {
account[_account] &= bytes32(~maskAccountPeriod);
account[_account] |= bytes32((_period << shiftAccountPeriod) & maskAccountPeriod);
incrementRedistributionParticipants();
return true;
}
// Determine whether the unit number is rounded down, rounded up or evenly divides.
// Returns 0 if evenly distributed, or the remainder as a positive number
// A _numParts value 0 will be interpreted as the value 1
function remainder(uint256 _numParts, uint256 _sumWhole) public pure returns (uint256) {
uint256 unit;
uint256 truncatedResult;
if (_numParts == 0) { // no division by zero please
revert('ERR_NUMPARTS_ZERO');
}
require(_numParts < _sumWhole); // At least you are never LESS than the sum of your parts. Think about that.
unit = _sumWhole / _numParts;
truncatedResult = unit * _numParts;
return _sumWhole - truncatedResult;
}
// Called in the edge case where participant number is 0. It will override the participant count to 1.
// Returns the remainder sent to the sink address
function applyDefaultRedistribution(bytes32 _redistribution) private returns (uint256) {
uint256 redistributionSupply;
uint256 redistributionPeriod;
uint256 unit;
uint256 truncatedResult;
redistributionSupply = toRedistributionSupply(_redistribution);
unit = (redistributionSupply * taxLevel) / 1000000;
truncatedResult = (unit * 1000000) / taxLevel;
if (truncatedResult < redistributionSupply) {
redistributionPeriod = toRedistributionPeriod(_redistribution); // since we reuse period here, can possibly be optimized by passing period instead
redistributions[redistributionPeriod-1] &= bytes32(~maskRedistributionParticipants); // just to be safe, zero out all participant count data, in this case there will be only one
redistributions[redistributionPeriod-1] |= bytes32(maskRedistributionIsFractional | (1 << shiftRedistributionParticipants));
}
increaseBaseBalance(sinkAddress, unit / ppmDivider);
return unit;
}
// sets the remainder bit for the given period and books the remainder to the sink address balance
// returns false if no change was made
function applyRemainderOnPeriod(uint256 _remainder, uint256 _period) private returns (bool) {
uint256 periodSupply;
if (_remainder == 0) {
return false;
}
// TODO: is this needed?
redistributions[_period-1] |= bytes32(maskRedistributionIsFractional);
periodSupply = toRedistributionSupply(redistributions[_period-1]);
increaseBaseBalance(sinkAddress, periodSupply - _remainder);
return true;
}
// Calculate and cache the demurrage value corresponding to the (period of the) time of the method call
function applyDemurrage() public returns (bool) {
uint128 epochPeriodCount;
uint128 periodCount;
uint256 lastDemurrageAmount;
uint256 newDemurrageAmount;
epochPeriodCount = actualPeriod();
periodCount = epochPeriodCount - demurragePeriod;
if (periodCount == 0) {
return false;
}
lastDemurrageAmount = demurrageAmount;
demurrageAmount = uint128(decayBy(lastDemurrageAmount, periodCount));
demurragePeriod = epochPeriodCount;
emit Decayed(epochPeriodCount, periodCount, lastDemurrageAmount, demurrageAmount);
return true;
}
// Return timestamp of start of period threshold
function getPeriodTimeDelta(uint256 _periodCount) public view returns (uint256) {
return periodStart + (_periodCount * periodDuration);
}
// Amount of demurrage cycles inbetween the current timestamp and the given target time
function demurrageCycles(uint256 _target) public view returns (uint256) {
return (block.timestamp - _target) / 60;
}
// Recalculate the demurrage modifier for the new period
// After this, all REPORTED balances will have been reduced by the corresponding ratio (but the effecive totalsupply stays the same)
function changePeriod() public returns (bool) {
bytes32 currentRedistribution;
bytes32 nextRedistribution;
uint256 currentPeriod;
uint256 currentParticipants;
uint256 currentRemainder;
uint256 currentDemurrageAmount;
uint256 nextRedistributionDemurrage;
uint256 demurrageCounts;
uint256 periodTimestamp;
uint256 nextPeriod;
currentRedistribution = checkPeriod();
if (currentRedistribution == bytes32(0x00)) {
return false;
}
currentPeriod = toRedistributionPeriod(currentRedistribution);
nextPeriod = currentPeriod + 1;
periodTimestamp = getPeriodTimeDelta(currentPeriod);
applyDemurrage();
currentDemurrageAmount = demurrageAmount;
demurrageCounts = demurrageCycles(periodTimestamp);
if (demurrageCounts > 0) {
nextRedistributionDemurrage = growBy(currentDemurrageAmount, demurrageCounts) / ppmDivider;
} else {
nextRedistributionDemurrage = currentDemurrageAmount / ppmDivider;
}
nextRedistribution = toRedistribution(0, nextRedistributionDemurrage, totalSupply, nextPeriod);
redistributions.push(nextRedistribution);
currentParticipants = toRedistributionParticipants(currentRedistribution);
if (currentParticipants == 0) {
currentRemainder = applyDefaultRedistribution(currentRedistribution);
} else {
currentRemainder = remainder(currentParticipants, totalSupply); // we can use totalSupply directly because it will always be the same as the recorded supply on the current redistribution
applyRemainderOnPeriod(currentRemainder, currentPeriod);
}
emit Period(nextPeriod);
return true;
}
// Reverse a value reduced by demurrage by the given period to its original value
function growBy(uint256 _value, uint256 _period) public view returns (uint256) {
uint256 valueFactor;
uint256 truncatedTaxLevel;
valueFactor = 1000000;
truncatedTaxLevel = taxLevel / ppmDivider;
for (uint256 i = 0; i < _period; i++) {
valueFactor = valueFactor + ((valueFactor * truncatedTaxLevel) / 1000000);
}
return (valueFactor * _value) / 1000000;
}
// Calculate a value reduced by demurrage by the given period
// TODO: higher precision if possible
function decayBy(uint256 _value, uint256 _period) public view returns (uint256) {
uint256 valueFactor;
uint256 truncatedTaxLevel;
valueFactor = 1000000;
truncatedTaxLevel = taxLevel / ppmDivider;
for (uint256 i = 0; i < _period; i++) {
valueFactor = valueFactor - ((valueFactor * truncatedTaxLevel) / 1000000);
}
return (valueFactor * _value) / 1000000;
}
// If the given account is participating in a period and that period has been crossed
// THEN increase the base value of the account with its share of the value reduction of the period
function applyRedistributionOnAccount(address _account) public returns (bool) {
bytes32 periodRedistribution;
uint256 supply;
uint256 participants;
uint256 baseValue;
uint256 value;
uint256 period;
uint256 demurrage;
period = accountPeriod(_account);
if (period == 0 || period >= actualPeriod()) {
return false;
}
periodRedistribution = redistributions[period-1];
participants = toRedistributionParticipants(periodRedistribution);
if (participants == 0) {
return false;
}
supply = toRedistributionSupply(periodRedistribution);
demurrage = toRedistributionDemurrageModifier(periodRedistribution);
baseValue = ((supply / participants) * (taxLevel / 1000000)) / ppmDivider;
value = (baseValue * demurrage) / 1000000;
// zero out period for the account
account[_account] &= bytes32(~maskAccountPeriod);
increaseBaseBalance(_account, value);
emit Redistribution(_account, period, value);
return true;
}
// Inflates the given amount according to the current demurrage modifier
function toBaseAmount(uint256 _value) public view returns (uint256) {
//return (_value * ppmDivider * 1000000) / toDemurrageAmount(demurrageModifier);
return (_value * ppmDivider * 1000000) / demurrageAmount;
}
// Implements ERC20, triggers tax and/or redistribution
function approve(address _spender, uint256 _value) public returns (bool) {
uint256 baseValue;
changePeriod();
applyRedistributionOnAccount(msg.sender);
baseValue = toBaseAmount(_value);
allowance[msg.sender][_spender] += baseValue;
emit Approval(msg.sender, _spender, _value);
return true;
}
// Implements ERC20, triggers tax and/or redistribution
function transfer(address _to, uint256 _value) public returns (bool) {
uint256 baseValue;
bool result;
changePeriod();
applyRedistributionOnAccount(msg.sender);
baseValue = toBaseAmount(_value);
result = transferBase(msg.sender, _to, baseValue);
emit Transfer(msg.sender, _to, _value);
return result;
}
// Implements ERC20, triggers tax and/or redistribution
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
uint256 baseValue;
bool result;
changePeriod();
applyRedistributionOnAccount(msg.sender);
baseValue = toBaseAmount(_value);
require(allowance[_from][msg.sender] >= baseValue);
result = transferBase(_from, _to, baseValue);
emit Transfer(_from, _to, _value);
return result;
}
// ERC20 transfer backend for transfer, transferFrom
function transferBase(address _from, address _to, uint256 _value) private returns (bool) {
uint256 period;
decreaseBaseBalance(_from, _value);
increaseBaseBalance(_to, _value);
period = actualPeriod();
if (_value >= minimumParticipantSpend && accountPeriod(_from) != period && _from != _to) {
registerAccountPeriod(_from, period);
}
return true;
}
// Implements EIP173
function transferOwnership(address _newOwner) public returns (bool) {
require(msg.sender == owner);
newOwner = _newOwner;
}
// Implements OwnedAccepter
function acceptOwnership() public returns (bool) {
address oldOwner;
require(msg.sender == newOwner);
oldOwner = owner;
owner = newOwner;
newOwner = address(0);
emit OwnershipTransferred(oldOwner, owner);
}
// Implements EIP165
function supportsInterface(bytes4 _sum) public pure returns (bool) {
if (_sum == 0xc6bb4b70) { // ERC20
return true;
}
if (_sum == 0x449a52f8) { // Minter
return true;
}
if (_sum == 0x01ffc9a7) { // EIP165
return true;
}
if (_sum == 0x9493f8b2) { // EIP173
return true;
}
if (_sum == 0x37a47be4) { // OwnedAccepter
return true;
}
return false;
}
}

2
solidity/DemurrageTokenMultiNocap.sol
View File

@ -2,7 +2,7 @@ pragma solidity > 0.6.11;
// SPDX-License-Identifier: GPL-3.0-or-later
contract RedistributedDemurrageToken {
contract DemurrageTokenMultiNocap {
// Redistribution bit field, with associated shifts and masks
// (Uses sub-byte boundaries)

609
solidity/DemurrageTokenSingleNocap.sol Normal file
View File

@ -0,0 +1,609 @@
pragma solidity > 0.6.11;
// SPDX-License-Identifier: GPL-3.0-or-later
contract DemurrageTokenSingleNocap {
// Redistribution bit field, with associated shifts and masks
// (Uses sub-byte boundaries)
bytes32[] public redistributions; // uint1(isFractional) | uint95(unused) | uint20(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
uint8 constant shiftRedistributionPeriod = 0;
uint256 constant maskRedistributionPeriod = 0x00000000000000000000000000000000000000000000000000000000ffffffff; // (1 << 32) - 1
uint8 constant shiftRedistributionValue = 32;
uint256 constant maskRedistributionValue = 0x00000000000000000000000000000000000000ffffffffffffffffff00000000; // ((1 << 72) - 1) << 32
uint8 constant shiftRedistributionParticipants = 104;
uint256 constant maskRedistributionParticipants = 0x00000000000000000000000000000fffffffff00000000000000000000000000; // ((1 << 36) - 1) << 104
uint8 constant shiftRedistributionDemurrage = 140;
uint256 constant maskRedistributionDemurrage = 0x000000000000000000000000fffff00000000000000000000000000000000000; // ((1 << 20) - 1) << 140
uint8 constant shiftRedistributionIsFractional = 255;
uint256 constant maskRedistributionIsFractional = 0x8000000000000000000000000000000000000000000000000000000000000000; // 1 << 255
// Account bit field, with associated shifts and masks
// Mirrors structure of redistributions for consistency
mapping (address => bytes32) account; // uint152(unused) | uint32(period) | uint72(value)
uint8 constant shiftAccountValue = 0;
uint256 constant maskAccountValue = 0x0000000000000000000000000000000000000000000000ffffffffffffffffff; // (1 << 72) - 1
uint8 constant shiftAccountPeriod = 72;
uint256 constant maskAccountPeriod = 0x00000000000000000000000000000000000000ffffffff000000000000000000; // ((1 << 32) - 1) << 72
// Cached demurrage amount, ppm with 38 digit resolution
uint128 public demurrageAmount;
// Cached demurrage period; the period for which demurrageAmount was calculated
uint128 public demurragePeriod;
// Implements EIP172
address public owner;
address newOwner;
// Implements ERC20
string public name;
// Implements ERC20
string public symbol;
// Implements ERC20
uint256 public decimals;
// Implements ERC20
uint256 public totalSupply;
// Minimum amount of (demurraged) tokens an account must spend to participate in redistribution for a particular period
uint256 public minimumParticipantSpend;
// 128 bit resolution of the demurrage divisor
// (this constant x 1000000 is contained within 128 bits)
uint256 constant ppmDivider = 100000000000000000000000000000000;
// Timestamp of start of periods (time which contract constructor was called)
uint256 public immutable periodStart;
// Duration of a single redistribution period in seconds
uint256 public immutable periodDuration;
// Demurrage in ppm per minute
uint256 public immutable taxLevel;
// Addresses allowed to mint new tokens
mapping (address => bool) minter;
// Storage for ERC20 approve/transferFrom methods
mapping (address => mapping (address => uint256 ) ) allowance; // holder -> spender -> amount (amount is subject to demurrage)
// Address to send unallocated redistribution tokens
address sinkAddress;
// Implements ERC20
event Transfer(address indexed _from, address indexed _to, uint256 _value);
// Implements ERC20
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
// New tokens minted
event Mint(address indexed _minter, address indexed _beneficiary, uint256 _value);
// New demurrage cache milestone calculated
event Decayed(uint256 indexed _period, uint256 indexed _periodCount, uint256 indexed _oldAmount, uint256 _newAmount);
// When a new period threshold has been crossed
event Period(uint256 _period);
// Redistribution applied on a single eligible account
event Redistribution(address indexed _account, uint256 indexed _period, uint256 _value);
// Temporary event used in development, will be removed on prod
event Debug(bytes32 _foo);
// EIP173
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); // EIP173
constructor(string memory _name, string memory _symbol, uint8 _decimals, uint256 _taxLevelMinute, uint256 _periodMinutes, address _defaultSinkAddress) public {
// ACL setup
owner = msg.sender;
minter[owner] = true;
// ERC20 setup
name = _name;
symbol = _symbol;
decimals = _decimals;
// Demurrage setup
periodStart = block.timestamp;
periodDuration = _periodMinutes * 60;
demurrageAmount = uint128(ppmDivider * 1000000); // Represents 38 decimal places
demurragePeriod = 1;
taxLevel = _taxLevelMinute; // Represents 38 decimal places
bytes32 initialRedistribution = toRedistribution(0, 1000000, 0, 1);
redistributions.push(initialRedistribution);
// Misc settings
sinkAddress = _defaultSinkAddress;
minimumParticipantSpend = 10 ** uint256(_decimals);
}
// Given address will be allowed to call the mintTo() function
function addMinter(address _minter) public returns (bool) {
require(msg.sender == owner);
minter[_minter] = true;
return true;
}
// Given address will no longer be allowed to call the mintTo() function
function removeMinter(address _minter) public returns (bool) {
require(msg.sender == owner || _minter == msg.sender);
minter[_minter] = false;
return true;
}
/// Implements ERC20
function balanceOf(address _account) public view returns (uint256) {
uint256 baseBalance;
uint256 currentDemurragedAmount;
uint256 periodCount;
baseBalance = baseBalanceOf(_account);
periodCount = actualPeriod() - demurragePeriod;
currentDemurragedAmount = uint128(decayBy(demurrageAmount, periodCount));
return (baseBalance * currentDemurragedAmount) / (ppmDivider * 1000000);
}
/// Balance unmodified by demurrage
function baseBalanceOf(address _account) public view returns (uint256) {
return uint256(account[_account]) & maskAccountValue;
//return uint256(account[_account]);
}
/// Increases base balance for a single account
function increaseBaseBalance(address _account, uint256 _delta) private returns (bool) {
uint256 oldBalance;
uint256 newBalance;
uint256 workAccount;
workAccount = uint256(account[_account]);
if (_delta == 0) {
return false;
}
oldBalance = baseBalanceOf(_account);
newBalance = oldBalance + _delta;
require(uint160(newBalance) > uint160(oldBalance), 'ERR_WOULDWRAP'); // revert if increase would result in a wrapped value
workAccount &= (~maskAccountValue);
workAccount |= (newBalance & maskAccountValue);
return true;
}
/// Decreases base balance for a single account
function decreaseBaseBalance(address _account, uint256 _delta) private returns (bool) {
uint256 oldBalance;
uint256 newBalance;
uint256 workAccount;
workAccount = uint256(account[_account]);
if (_delta == 0) {
return false;
}
oldBalance = baseBalanceOf(_account);
require(oldBalance >= _delta, 'ERR_OVERSPEND'); // overspend guard
newBalance = oldBalance - _delta;
workAccount &= (~maskAccountValue);
workAccount |= (newBalance & maskAccountValue);
account[_account] = bytes32(workAccount);
return true;
}
// Creates new tokens out of thin air, and allocates them to the given address
// Triggers tax
function mintTo(address _beneficiary, uint256 _amount) external returns (bool) {
uint256 baseAmount;
require(minter[msg.sender]);
changePeriod();
baseAmount = _amount;
totalSupply += _amount;
increaseBaseBalance(_beneficiary, baseAmount);
emit Mint(msg.sender, _beneficiary, _amount);
saveRedistributionSupply();
return true;
}
// Deserializes the redistribution word
// uint1(isFractional) | uint95(unused) | uint20(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
function toRedistribution(uint256 _participants, uint256 _demurrageModifierPpm, uint256 _value, uint256 _period) private pure returns(bytes32) {
bytes32 redistribution;
redistribution |= bytes32((_demurrageModifierPpm << shiftRedistributionDemurrage) & maskRedistributionDemurrage);
redistribution |= bytes32((_participants << shiftRedistributionParticipants) & maskRedistributionParticipants);
redistribution |= bytes32((_value << shiftRedistributionValue) & maskRedistributionValue);
redistribution |= bytes32(_period & maskRedistributionPeriod);
return redistribution;
}
// Serializes the demurrage period part of the redistribution word
function toRedistributionPeriod(bytes32 redistribution) public pure returns (uint256) {
return uint256(redistribution) & maskRedistributionPeriod;
}
// Serializes the supply part of the redistribution word
function toRedistributionSupply(bytes32 redistribution) public pure returns (uint256) {
return (uint256(redistribution) & maskRedistributionValue) >> shiftRedistributionValue;
}
// Serializes the number of participants part of the redistribution word
function toRedistributionParticipants(bytes32 redistribution) public pure returns (uint256) {
return (uint256(redistribution) & maskRedistributionParticipants) >> shiftRedistributionParticipants;
}
// Serializes the number of participants part of the redistribution word
function toRedistributionDemurrageModifier(bytes32 redistribution) public pure returns (uint256) {
return (uint256(redistribution) & maskRedistributionDemurrage) >> shiftRedistributionDemurrage;
}
// Client accessor to the redistributions array length
function redistributionCount() public view returns (uint256) {
return redistributions.length;
}
// Add number of participants for the current redistribution period by one
function incrementRedistributionParticipants() private returns (bool) {
bytes32 currentRedistribution;
uint256 tmpRedistribution;
uint256 participants;
currentRedistribution = redistributions[redistributions.length-1];
participants = toRedistributionParticipants(currentRedistribution) + 1;
tmpRedistribution = uint256(currentRedistribution);
tmpRedistribution &= (~maskRedistributionParticipants);
tmpRedistribution |= ((participants << shiftRedistributionParticipants) & maskRedistributionParticipants);
redistributions[redistributions.length-1] = bytes32(tmpRedistribution);
return true;
}
// Save the current total supply amount to the current redistribution period
function saveRedistributionSupply() private returns (bool) {
uint256 currentRedistribution;
currentRedistribution = uint256(redistributions[redistributions.length-1]);
currentRedistribution &= (~maskRedistributionValue);
currentRedistribution |= (totalSupply << shiftRedistributionValue);
redistributions[redistributions.length-1] = bytes32(currentRedistribution);
return true;
}
// Get the demurrage period of the current block number
function actualPeriod() public view returns (uint128) {
return uint128((block.timestamp - periodStart) / periodDuration + 1);
}
// Add an entered demurrage period to the redistribution array
function checkPeriod() private view returns (bytes32) {
bytes32 lastRedistribution;
uint256 currentPeriod;
lastRedistribution = redistributions[redistributions.length-1];
currentPeriod = this.actualPeriod();
if (currentPeriod <= toRedistributionPeriod(lastRedistribution)) {
return bytes32(0x00);
}
return lastRedistribution;
}
// Deserialize the pemurrage period for the given account is participating in
function accountPeriod(address _account) public view returns (uint256) {
return (uint256(account[_account]) & maskAccountPeriod) >> shiftAccountPeriod;
}
// Save the given demurrage period as the currently participation period for the given address
function registerAccountPeriod(address _account, uint256 _period) private returns (bool) {
account[_account] &= bytes32(~maskAccountPeriod);
account[_account] |= bytes32((_period << shiftAccountPeriod) & maskAccountPeriod);
incrementRedistributionParticipants();
return true;
}
// Determine whether the unit number is rounded down, rounded up or evenly divides.
// Returns 0 if evenly distributed, or the remainder as a positive number
// A _numParts value 0 will be interpreted as the value 1
function remainder(uint256 _numParts, uint256 _sumWhole) public pure returns (uint256) {
uint256 unit;
uint256 truncatedResult;
if (_numParts == 0) { // no division by zero please
revert('ERR_NUMPARTS_ZERO');
}
require(_numParts < _sumWhole); // At least you are never LESS than the sum of your parts. Think about that.
unit = _sumWhole / _numParts;
truncatedResult = unit * _numParts;
return _sumWhole - truncatedResult;
}
// Returns the amount sent to the sink address
function applyDefaultRedistribution(bytes32 _redistribution) private returns (uint256) {
uint256 redistributionSupply;
uint256 redistributionPeriod;
uint256 unit;
uint256 truncatedResult;
redistributionSupply = toRedistributionSupply(_redistribution);
unit = (redistributionSupply * taxLevel) / 1000000;
truncatedResult = (unit * 1000000) / taxLevel;
if (truncatedResult < redistributionSupply) {
redistributionPeriod = toRedistributionPeriod(_redistribution); // since we reuse period here, can possibly be optimized by passing period instead
redistributions[redistributionPeriod-1] &= bytes32(~maskRedistributionParticipants); // just to be safe, zero out all participant count data, in this case there will be only one
redistributions[redistributionPeriod-1] |= bytes32(maskRedistributionIsFractional | (1 << shiftRedistributionParticipants));
}
increaseBaseBalance(sinkAddress, unit / ppmDivider);
return unit;
}
// sets the remainder bit for the given period and books the remainder to the sink address balance
// returns false if no change was made
function applyRemainderOnPeriod(uint256 _remainder, uint256 _period) private returns (bool) {
uint256 periodSupply;
if (_remainder == 0) {
return false;
}
// TODO: is this needed?
redistributions[_period-1] |= bytes32(maskRedistributionIsFractional);
periodSupply = toRedistributionSupply(redistributions[_period-1]);
increaseBaseBalance(sinkAddress, periodSupply - _remainder);
return true;
}
// Calculate and cache the demurrage value corresponding to the (period of the) time of the method call
function applyDemurrage() public returns (bool) {
uint128 epochPeriodCount;
uint128 periodCount;
uint256 lastDemurrageAmount;
uint256 newDemurrageAmount;
epochPeriodCount = actualPeriod();
periodCount = epochPeriodCount - demurragePeriod;
if (periodCount == 0) {
return false;
}
lastDemurrageAmount = demurrageAmount;
demurrageAmount = uint128(decayBy(lastDemurrageAmount, periodCount));
demurragePeriod = epochPeriodCount;
emit Decayed(epochPeriodCount, periodCount, lastDemurrageAmount, demurrageAmount);
return true;
}
// Return timestamp of start of period threshold
function getPeriodTimeDelta(uint256 _periodCount) public view returns (uint256) {
return periodStart + (_periodCount * periodDuration);
}
// Amount of demurrage cycles inbetween the current timestamp and the given target time
function demurrageCycles(uint256 _target) public view returns (uint256) {
return (block.timestamp - _target) / 60;
}
// Recalculate the demurrage modifier for the new period
function changePeriod() public returns (bool) {
bytes32 currentRedistribution;
bytes32 nextRedistribution;
uint256 currentPeriod;
uint256 currentParticipants;
uint256 currentRemainder;
uint256 currentDemurrageAmount;
uint256 nextRedistributionDemurrage;
uint256 demurrageCounts;
uint256 periodTimestamp;
uint256 nextPeriod;
currentRedistribution = checkPeriod();
if (currentRedistribution == bytes32(0x00)) {
return false;
}
currentPeriod = toRedistributionPeriod(currentRedistribution);
nextPeriod = currentPeriod + 1;
periodTimestamp = getPeriodTimeDelta(currentPeriod);
applyDemurrage();
currentDemurrageAmount = demurrageAmount;
demurrageCounts = demurrageCycles(periodTimestamp);
if (demurrageCounts > 0) {
nextRedistributionDemurrage = growBy(currentDemurrageAmount, demurrageCounts) / ppmDivider;
} else {
nextRedistributionDemurrage = currentDemurrageAmount / ppmDivider;
}
nextRedistribution = toRedistribution(0, nextRedistributionDemurrage, totalSupply, nextPeriod);
redistributions.push(nextRedistribution);
//currentParticipants = toRedistributionParticipants(currentRedistribution);
//if (currentParticipants == 0) {
currentRemainder = applyDefaultRedistribution(currentRedistribution);
//} else {
// currentRemainder = remainder(currentParticipants, totalSupply); // we can use totalSupply directly because it will always be the same as the recorded supply on the current redistribution
// applyRemainderOnPeriod(currentRemainder, currentPeriod);
//}
emit Period(nextPeriod);
return true;
}
// Reverse a value reduced by demurrage by the given period to its original value
function growBy(uint256 _value, uint256 _period) public view returns (uint256) {
uint256 valueFactor;
uint256 truncatedTaxLevel;
valueFactor = 1000000;
truncatedTaxLevel = taxLevel / ppmDivider;
for (uint256 i = 0; i < _period; i++) {
valueFactor = valueFactor + ((valueFactor * truncatedTaxLevel) / 1000000);
}
return (valueFactor * _value) / 1000000;
}
// Calculate a value reduced by demurrage by the given period
// TODO: higher precision if possible
function decayBy(uint256 _value, uint256 _period) public view returns (uint256) {
uint256 valueFactor;
uint256 truncatedTaxLevel;
valueFactor = 1000000;
truncatedTaxLevel = taxLevel / ppmDivider;
for (uint256 i = 0; i < _period; i++) {
valueFactor = valueFactor - ((valueFactor * truncatedTaxLevel) / 1000000);
}
return (valueFactor * _value) / 1000000;
}
// If the given account is participating in a period and that period has been crossed
// THEN increase the base value of the account with its share of the value reduction of the period
function applyRedistributionOnAccount(address _account) public returns (bool) {
// bytes32 periodRedistribution;
// uint256 supply;
// uint256 participants;
// uint256 baseValue;
// uint256 value;
uint256 period;
// uint256 demurrage;
//
period = accountPeriod(_account);
if (period == 0 || period >= actualPeriod()) {
return false;
}
// periodRedistribution = redistributions[period-1];
// participants = toRedistributionParticipants(periodRedistribution);
// if (participants == 0) {
// return false;
// }
//
// supply = toRedistributionSupply(periodRedistribution);
// demurrage = toRedistributionDemurrageModifier(periodRedistribution);
// baseValue = ((supply / participants) * (taxLevel / 1000000)) / ppmDivider;
// value = (baseValue * demurrage) / 1000000;
//
// // zero out period for the account
account[_account] &= bytes32(~maskAccountPeriod);
// increaseBaseBalance(_account, value);
//
// emit Redistribution(_account, period, value);
return true;
}
// Inflates the given amount according to the current demurrage modifier
function toBaseAmount(uint256 _value) public view returns (uint256) {
//return (_value * ppmDivider * 1000000) / toDemurrageAmount(demurrageModifier);
return (_value * ppmDivider * 1000000) / demurrageAmount;
}
// Implements ERC20, triggers tax and/or redistribution
function approve(address _spender, uint256 _value) public returns (bool) {
uint256 baseValue;
changePeriod();
//applyRedistributionOnAccount(msg.sender);
baseValue = toBaseAmount(_value);
allowance[msg.sender][_spender] += baseValue;
emit Approval(msg.sender, _spender, _value);
return true;
}
// Implements ERC20, triggers tax and/or redistribution
function transfer(address _to, uint256 _value) public returns (bool) {
uint256 baseValue;
bool result;
changePeriod();
//applyRedistributionOnAccount(msg.sender);
baseValue = toBaseAmount(_value);
result = transferBase(msg.sender, _to, baseValue);
emit Transfer(msg.sender, _to, _value);
return result;
}
// Implements ERC20, triggers tax and/or redistribution
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
uint256 baseValue;
bool result;
changePeriod();
//applyRedistributionOnAccount(msg.sender);
baseValue = toBaseAmount(_value);
require(allowance[_from][msg.sender] >= baseValue);
result = transferBase(_from, _to, baseValue);
emit Transfer(_from, _to, _value);
return result;
}
// ERC20 transfer backend for transfer, transferFrom
function transferBase(address _from, address _to, uint256 _value) private returns (bool) {
uint256 period;
decreaseBaseBalance(_from, _value);
increaseBaseBalance(_to, _value);
period = actualPeriod();
if (_value >= minimumParticipantSpend && accountPeriod(_from) != period && _from != _to) {
registerAccountPeriod(_from, period);
}
return true;
}
// Implements EIP173
function transferOwnership(address _newOwner) public returns (bool) {
require(msg.sender == owner);
newOwner = _newOwner;
}
// Implements OwnedAccepter
function acceptOwnership() public returns (bool) {
address oldOwner;
require(msg.sender == newOwner);
oldOwner = owner;
owner = newOwner;
newOwner = address(0);
emit OwnershipTransferred(oldOwner, owner);
}
// Implements EIP165
function supportsInterface(bytes4 _sum) public pure returns (bool) {
if (_sum == 0xc6bb4b70) { // ERC20
return true;
}
if (_sum == 0x449a52f8) { // Minter
return true;
}
if (_sum == 0x01ffc9a7) { // EIP165
return true;
}
if (_sum == 0x9493f8b2) { // EIP173
return true;
}
if (_sum == 0x37a47be4) { // OwnedAccepter
return true;
}
return false;
}
}

20
solidity/Makefile
View File

@ -1,16 +1,32 @@
SOLC = /usr/bin/solc
all:
all: multi_nocap multi_cap single_nocap
multi_nocap:
$(SOLC) DemurrageTokenMultiNocap.sol --abi --evm-version byzantium | awk 'NR>3' > DemurrageTokenMultiNocap.json
$(SOLC) DemurrageTokenMultiNocap.sol --bin --evm-version byzantium | awk 'NR>3' > DemurrageTokenMultiNocap.bin
truncate -s -1 DemurrageTokenMultiCap.bin
multi_cap:
$(SOLC) DemurrageTokenMultiCap.sol --abi --evm-version byzantium | awk 'NR>3' > DemurrageTokenMultiCap.json
$(SOLC) DemurrageTokenMultiCap.sol --bin --evm-version byzantium | awk 'NR>3' > DemurrageTokenMultiCap.bin
truncate -s -1 DemurrageTokenMultiNocap.bin
multi: multi_nocap multi_cap
single_nocap:
$(SOLC) DemurrageTokenSingleNocap.sol --abi --evm-version byzantium | awk 'NR>3' > DemurrageTokenSingleNocap.json
$(SOLC) DemurrageTokenSingleNocap.sol --bin --evm-version byzantium | awk 'NR>3' > DemurrageTokenSingleNocap.bin
truncate -s -1 DemurrageTokenSingleNocap.bin
test: all
python ../python/tests/test_basic.py
python ../python/tests/test_period.py
python ../python/tests/test_redistribution.py
python ../python/tests/test_pure.py
install: all
cp -v DemurrageTokenMultiNocap.{json,bin} ../python/sarafu_token/data/
cp -v DemurrageToken*.{json,bin} ../python/erc20_demurrage_token/data/
.PHONY: test install