Contract Source Code:
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
pragma solidity 0.5.12;
contract BColor {
function getColor()
external view
returns (bytes32);
}
contract BBronze is BColor {
function getColor()
external view
returns (bytes32) {
return bytes32("BRONZE");
}
}
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
pragma solidity 0.5.12;
import "./BColor.sol";
contract BConst is BBronze {
uint public constant BONE = 10**18;
uint public constant MIN_BOUND_TOKENS = 2;
uint public constant MAX_BOUND_TOKENS = 8;
uint public constant MIN_FEE = BONE / 10**6;
uint public constant MAX_FEE = BONE / 10;
uint public constant EXIT_FEE = 0;
uint public constant MIN_WEIGHT = BONE;
uint public constant MAX_WEIGHT = BONE * 50;
uint public constant MAX_TOTAL_WEIGHT = BONE * 50;
uint public constant MIN_BALANCE = BONE / 10**12;
uint public constant INIT_POOL_SUPPLY = BONE * 100;
uint public constant MIN_BPOW_BASE = 1 wei;
uint public constant MAX_BPOW_BASE = (2 * BONE) - 1 wei;
uint public constant BPOW_PRECISION = BONE / 10**10;
uint public constant MAX_IN_RATIO = BONE / 2;
uint public constant MAX_OUT_RATIO = (BONE / 3) + 1 wei;
}
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
pragma solidity 0.5.12;
import "./BNum.sol";
contract BMath is BBronze, BConst, BNum {
/**********************************************************************************************
// calcSpotPrice //
// sP = spotPrice //
// bI = tokenBalanceIn ( bI / wI ) 1 //
// bO = tokenBalanceOut sP = ----------- * ---------- //
// wI = tokenWeightIn ( bO / wO ) ( 1 - sF ) //
// wO = tokenWeightOut //
// sF = swapFee //
**********************************************************************************************/
function calcSpotPrice(
uint tokenBalanceIn,
uint tokenWeightIn,
uint tokenBalanceOut,
uint tokenWeightOut,
uint swapFee
)
public pure
returns (uint spotPrice)
{
uint numer = bdiv(tokenBalanceIn, tokenWeightIn);
uint denom = bdiv(tokenBalanceOut, tokenWeightOut);
uint ratio = bdiv(numer, denom);
uint scale = bdiv(BONE, bsub(BONE, swapFee));
return (spotPrice = bmul(ratio, scale));
}
/**********************************************************************************************
// calcOutGivenIn //
// aO = tokenAmountOut //
// bO = tokenBalanceOut //
// bI = tokenBalanceIn / / bI \ (wI / wO) \ //
// aI = tokenAmountIn aO = bO * | 1 - | -------------------------- | ^ | //
// wI = tokenWeightIn \ \ ( bI + ( aI * ( 1 - sF )) / / //
// wO = tokenWeightOut //
// sF = swapFee //
**********************************************************************************************/
function calcOutGivenIn(
uint tokenBalanceIn,
uint tokenWeightIn,
uint tokenBalanceOut,
uint tokenWeightOut,
uint tokenAmountIn,
uint swapFee
)
public pure
returns (uint tokenAmountOut)
{
uint weightRatio = bdiv(tokenWeightIn, tokenWeightOut);
uint adjustedIn = bsub(BONE, swapFee);
adjustedIn = bmul(tokenAmountIn, adjustedIn);
uint y = bdiv(tokenBalanceIn, badd(tokenBalanceIn, adjustedIn));
uint foo = bpow(y, weightRatio);
uint bar = bsub(BONE, foo);
tokenAmountOut = bmul(tokenBalanceOut, bar);
return tokenAmountOut;
}
/**********************************************************************************************
// calcInGivenOut //
// aI = tokenAmountIn //
// bO = tokenBalanceOut / / bO \ (wO / wI) \ //
// bI = tokenBalanceIn bI * | | ------------ | ^ - 1 | //
// aO = tokenAmountOut aI = \ \ ( bO - aO ) / / //
// wI = tokenWeightIn -------------------------------------------- //
// wO = tokenWeightOut ( 1 - sF ) //
// sF = swapFee //
**********************************************************************************************/
function calcInGivenOut(
uint tokenBalanceIn,
uint tokenWeightIn,
uint tokenBalanceOut,
uint tokenWeightOut,
uint tokenAmountOut,
uint swapFee
)
public pure
returns (uint tokenAmountIn)
{
uint weightRatio = bdiv(tokenWeightOut, tokenWeightIn);
uint diff = bsub(tokenBalanceOut, tokenAmountOut);
uint y = bdiv(tokenBalanceOut, diff);
uint foo = bpow(y, weightRatio);
foo = bsub(foo, BONE);
tokenAmountIn = bsub(BONE, swapFee);
tokenAmountIn = bdiv(bmul(tokenBalanceIn, foo), tokenAmountIn);
return tokenAmountIn;
}
/**********************************************************************************************
// calcPoolOutGivenSingleIn //
// pAo = poolAmountOut / \ //
// tAi = tokenAmountIn /// / // wI \ \\ \ wI \ //
// wI = tokenWeightIn //| tAi *| 1 - || 1 - -- | * sF || + tBi \ -- \ //
// tW = totalWeight pAo=|| \ \ \\ tW / // | ^ tW | * pS - pS //
// tBi = tokenBalanceIn \\ ------------------------------------- / / //
// pS = poolSupply \\ tBi / / //
// sF = swapFee \ / //
**********************************************************************************************/
function calcPoolOutGivenSingleIn(
uint tokenBalanceIn,
uint tokenWeightIn,
uint poolSupply,
uint totalWeight,
uint tokenAmountIn,
uint swapFee
)
public pure
returns (uint poolAmountOut)
{
// Charge the trading fee for the proportion of tokenAi
/// which is implicitly traded to the other pool tokens.
// That proportion is (1- weightTokenIn)
// tokenAiAfterFee = tAi * (1 - (1-weightTi) * poolFee);
uint normalizedWeight = bdiv(tokenWeightIn, totalWeight);
uint zaz = bmul(bsub(BONE, normalizedWeight), swapFee);
uint tokenAmountInAfterFee = bmul(tokenAmountIn, bsub(BONE, zaz));
uint newTokenBalanceIn = badd(tokenBalanceIn, tokenAmountInAfterFee);
uint tokenInRatio = bdiv(newTokenBalanceIn, tokenBalanceIn);
// uint newPoolSupply = (ratioTi ^ weightTi) * poolSupply;
uint poolRatio = bpow(tokenInRatio, normalizedWeight);
uint newPoolSupply = bmul(poolRatio, poolSupply);
poolAmountOut = bsub(newPoolSupply, poolSupply);
return poolAmountOut;
}
/**********************************************************************************************
// calcSingleInGivenPoolOut //
// tAi = tokenAmountIn //(pS + pAo)\ / 1 \\ //
// pS = poolSupply || --------- | ^ | --------- || * bI - bI //
// pAo = poolAmountOut \\ pS / \(wI / tW)// //
// bI = balanceIn tAi = -------------------------------------------- //
// wI = weightIn / wI \ //
// tW = totalWeight | 1 - ---- | * sF //
// sF = swapFee \ tW / //
**********************************************************************************************/
function calcSingleInGivenPoolOut(
uint tokenBalanceIn,
uint tokenWeightIn,
uint poolSupply,
uint totalWeight,
uint poolAmountOut,
uint swapFee
)
public pure
returns (uint tokenAmountIn)
{
uint normalizedWeight = bdiv(tokenWeightIn, totalWeight);
uint newPoolSupply = badd(poolSupply, poolAmountOut);
uint poolRatio = bdiv(newPoolSupply, poolSupply);
//uint newBalTi = poolRatio^(1/weightTi) * balTi;
uint boo = bdiv(BONE, normalizedWeight);
uint tokenInRatio = bpow(poolRatio, boo);
uint newTokenBalanceIn = bmul(tokenInRatio, tokenBalanceIn);
uint tokenAmountInAfterFee = bsub(newTokenBalanceIn, tokenBalanceIn);
// Do reverse order of fees charged in joinswap_ExternAmountIn, this way
// ``` pAo == joinswap_ExternAmountIn(Ti, joinswap_PoolAmountOut(pAo, Ti)) ```
//uint tAi = tAiAfterFee / (1 - (1-weightTi) * swapFee) ;
uint zar = bmul(bsub(BONE, normalizedWeight), swapFee);
tokenAmountIn = bdiv(tokenAmountInAfterFee, bsub(BONE, zar));
return tokenAmountIn;
}
/**********************************************************************************************
// calcSingleOutGivenPoolIn //
// tAo = tokenAmountOut / / \\ //
// bO = tokenBalanceOut / // pS - (pAi * (1 - eF)) \ / 1 \ \\ //
// pAi = poolAmountIn | bO - || ----------------------- | ^ | --------- | * b0 || //
// ps = poolSupply \ \\ pS / \(wO / tW)/ // //
// wI = tokenWeightIn tAo = \ \ // //
// tW = totalWeight / / wO \ \ //
// sF = swapFee * | 1 - | 1 - ---- | * sF | //
// eF = exitFee \ \ tW / / //
**********************************************************************************************/
function calcSingleOutGivenPoolIn(
uint tokenBalanceOut,
uint tokenWeightOut,
uint poolSupply,
uint totalWeight,
uint poolAmountIn,
uint swapFee
)
public pure
returns (uint tokenAmountOut)
{
uint normalizedWeight = bdiv(tokenWeightOut, totalWeight);
// charge exit fee on the pool token side
// pAiAfterExitFee = pAi*(1-exitFee)
uint poolAmountInAfterExitFee = bmul(poolAmountIn, bsub(BONE, EXIT_FEE));
uint newPoolSupply = bsub(poolSupply, poolAmountInAfterExitFee);
uint poolRatio = bdiv(newPoolSupply, poolSupply);
// newBalTo = poolRatio^(1/weightTo) * balTo;
uint tokenOutRatio = bpow(poolRatio, bdiv(BONE, normalizedWeight));
uint newTokenBalanceOut = bmul(tokenOutRatio, tokenBalanceOut);
uint tokenAmountOutBeforeSwapFee = bsub(tokenBalanceOut, newTokenBalanceOut);
// charge swap fee on the output token side
//uint tAo = tAoBeforeSwapFee * (1 - (1-weightTo) * swapFee)
uint zaz = bmul(bsub(BONE, normalizedWeight), swapFee);
tokenAmountOut = bmul(tokenAmountOutBeforeSwapFee, bsub(BONE, zaz));
return tokenAmountOut;
}
/**********************************************************************************************
// calcPoolInGivenSingleOut //
// pAi = poolAmountIn // / tAo \\ / wO \ \ //
// bO = tokenBalanceOut // | bO - -------------------------- |\ | ---- | \ //
// tAo = tokenAmountOut pS - || \ 1 - ((1 - (tO / tW)) * sF)/ | ^ \ tW / * pS | //
// ps = poolSupply \\ -----------------------------------/ / //
// wO = tokenWeightOut pAi = \\ bO / / //
// tW = totalWeight ------------------------------------------------------------- //
// sF = swapFee ( 1 - eF ) //
// eF = exitFee //
**********************************************************************************************/
function calcPoolInGivenSingleOut(
uint tokenBalanceOut,
uint tokenWeightOut,
uint poolSupply,
uint totalWeight,
uint tokenAmountOut,
uint swapFee
)
public pure
returns (uint poolAmountIn)
{
// charge swap fee on the output token side
uint normalizedWeight = bdiv(tokenWeightOut, totalWeight);
//uint tAoBeforeSwapFee = tAo / (1 - (1-weightTo) * swapFee) ;
uint zoo = bsub(BONE, normalizedWeight);
uint zar = bmul(zoo, swapFee);
uint tokenAmountOutBeforeSwapFee = bdiv(tokenAmountOut, bsub(BONE, zar));
uint newTokenBalanceOut = bsub(tokenBalanceOut, tokenAmountOutBeforeSwapFee);
uint tokenOutRatio = bdiv(newTokenBalanceOut, tokenBalanceOut);
//uint newPoolSupply = (ratioTo ^ weightTo) * poolSupply;
uint poolRatio = bpow(tokenOutRatio, normalizedWeight);
uint newPoolSupply = bmul(poolRatio, poolSupply);
uint poolAmountInAfterExitFee = bsub(poolSupply, newPoolSupply);
// charge exit fee on the pool token side
// pAi = pAiAfterExitFee/(1-exitFee)
poolAmountIn = bdiv(poolAmountInAfterExitFee, bsub(BONE, EXIT_FEE));
return poolAmountIn;
}
}
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
pragma solidity 0.5.12;
import "./BConst.sol";
contract BNum is BConst {
function btoi(uint a)
internal pure
returns (uint)
{
return a / BONE;
}
function bfloor(uint a)
internal pure
returns (uint)
{
return btoi(a) * BONE;
}
function badd(uint a, uint b)
internal pure
returns (uint)
{
uint c = a + b;
require(c >= a, "ERR_ADD_OVERFLOW");
return c;
}
function bsub(uint a, uint b)
internal pure
returns (uint)
{
(uint c, bool flag) = bsubSign(a, b);
require(!flag, "ERR_SUB_UNDERFLOW");
return c;
}
function bsubSign(uint a, uint b)
internal pure
returns (uint, bool)
{
if (a >= b) {
return (a - b, false);
} else {
return (b - a, true);
}
}
function bmul(uint a, uint b)
internal pure
returns (uint)
{
uint c0 = a * b;
require(a == 0 || c0 / a == b, "ERR_MUL_OVERFLOW");
uint c1 = c0 + (BONE / 2);
require(c1 >= c0, "ERR_MUL_OVERFLOW");
uint c2 = c1 / BONE;
return c2;
}
function bdiv(uint a, uint b)
internal pure
returns (uint)
{
require(b != 0, "ERR_DIV_ZERO");
uint c0 = a * BONE;
require(a == 0 || c0 / a == BONE, "ERR_DIV_INTERNAL"); // bmul overflow
uint c1 = c0 + (b / 2);
require(c1 >= c0, "ERR_DIV_INTERNAL"); // badd require
uint c2 = c1 / b;
return c2;
}
// DSMath.wpow
function bpowi(uint a, uint n)
internal pure
returns (uint)
{
uint z = n % 2 != 0 ? a : BONE;
for (n /= 2; n != 0; n /= 2) {
a = bmul(a, a);
if (n % 2 != 0) {
z = bmul(z, a);
}
}
return z;
}
// Compute b^(e.w) by splitting it into (b^e)*(b^0.w).
// Use `bpowi` for `b^e` and `bpowK` for k iterations
// of approximation of b^0.w
function bpow(uint base, uint exp)
internal pure
returns (uint)
{
require(base >= MIN_BPOW_BASE, "ERR_BPOW_BASE_TOO_LOW");
require(base <= MAX_BPOW_BASE, "ERR_BPOW_BASE_TOO_HIGH");
uint whole = bfloor(exp);
uint remain = bsub(exp, whole);
uint wholePow = bpowi(base, btoi(whole));
if (remain == 0) {
return wholePow;
}
uint partialResult = bpowApprox(base, remain, BPOW_PRECISION);
return bmul(wholePow, partialResult);
}
function bpowApprox(uint base, uint exp, uint precision)
internal pure
returns (uint)
{
// term 0:
uint a = exp;
(uint x, bool xneg) = bsubSign(base, BONE);
uint term = BONE;
uint sum = term;
bool negative = false;
// term(k) = numer / denom
// = (product(a - i - 1, i=1-->k) * x^k) / (k!)
// each iteration, multiply previous term by (a-(k-1)) * x / k
// continue until term is less than precision
for (uint i = 1; term >= precision; i++) {
uint bigK = i * BONE;
(uint c, bool cneg) = bsubSign(a, bsub(bigK, BONE));
term = bmul(term, bmul(c, x));
term = bdiv(term, bigK);
if (term == 0) break;
if (xneg) negative = !negative;
if (cneg) negative = !negative;
if (negative) {
sum = bsub(sum, term);
} else {
sum = badd(sum, term);
}
}
return sum;
}
}
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
pragma solidity 0.5.12;
import "./BToken.sol";
import "./BMath.sol";
contract BPool is BBronze, BToken, BMath {
struct Record {
bool bound; // is token bound to pool
uint index; // private
uint denorm; // denormalized weight
uint balance;
}
event LOG_SWAP(
address indexed caller,
address indexed tokenIn,
address indexed tokenOut,
uint256 tokenAmountIn,
uint256 tokenAmountOut
);
event LOG_JOIN(
address indexed caller,
address indexed tokenIn,
uint256 tokenAmountIn
);
event LOG_EXIT(
address indexed caller,
address indexed tokenOut,
uint256 tokenAmountOut
);
event LOG_CALL(
bytes4 indexed sig,
address indexed caller,
bytes data
) anonymous;
modifier _logs_() {
emit LOG_CALL(msg.sig, msg.sender, msg.data);
_;
}
modifier _lock_() {
require(!_mutex, "ERR_REENTRY");
_mutex = true;
_;
_mutex = false;
}
modifier _viewlock_() {
require(!_mutex, "ERR_REENTRY");
_;
}
bool private _mutex;
address private _factory; // BFactory address to push token exitFee to
address private _controller; // has CONTROL role
bool private _publicSwap; // true if PUBLIC can call SWAP functions
// `setSwapFee` and `finalize` require CONTROL
// `finalize` sets `PUBLIC can SWAP`, `PUBLIC can JOIN`
uint private _swapFee;
bool private _finalized;
address[] private _tokens;
mapping(address=>Record) private _records;
uint private _totalWeight;
constructor() public {
_controller = msg.sender;
_factory = msg.sender;
_swapFee = MIN_FEE;
_publicSwap = false;
_finalized = false;
}
function isPublicSwap()
external view
returns (bool)
{
return _publicSwap;
}
function isFinalized()
external view
returns (bool)
{
return _finalized;
}
function isBound(address t)
external view
returns (bool)
{
return _records[t].bound;
}
function getNumTokens()
external view
returns (uint)
{
return _tokens.length;
}
function getCurrentTokens()
external view _viewlock_
returns (address[] memory tokens)
{
return _tokens;
}
function getFinalTokens()
external view
_viewlock_
returns (address[] memory tokens)
{
require(_finalized, "ERR_NOT_FINALIZED");
return _tokens;
}
function getDenormalizedWeight(address token)
external view
_viewlock_
returns (uint)
{
require(_records[token].bound, "ERR_NOT_BOUND");
return _records[token].denorm;
}
function getTotalDenormalizedWeight()
external view
_viewlock_
returns (uint)
{
return _totalWeight;
}
function getNormalizedWeight(address token)
external view
_viewlock_
returns (uint)
{
require(_records[token].bound, "ERR_NOT_BOUND");
uint denorm = _records[token].denorm;
return bdiv(denorm, _totalWeight);
}
function getBalance(address token)
external view
_viewlock_
returns (uint)
{
require(_records[token].bound, "ERR_NOT_BOUND");
return _records[token].balance;
}
function getSwapFee()
external view
_viewlock_
returns (uint)
{
return _swapFee;
}
function getController()
external view
_viewlock_
returns (address)
{
return _controller;
}
function setSwapFee(uint swapFee)
external
_logs_
_lock_
{
require(!_finalized, "ERR_IS_FINALIZED");
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
require(swapFee >= MIN_FEE, "ERR_MIN_FEE");
require(swapFee <= MAX_FEE, "ERR_MAX_FEE");
_swapFee = swapFee;
}
function setController(address manager)
external
_logs_
_lock_
{
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
_controller = manager;
}
function setPublicSwap(bool public_)
external
_logs_
_lock_
{
require(!_finalized, "ERR_IS_FINALIZED");
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
_publicSwap = public_;
}
function finalize()
external
_logs_
_lock_
{
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
require(!_finalized, "ERR_IS_FINALIZED");
require(_tokens.length >= MIN_BOUND_TOKENS, "ERR_MIN_TOKENS");
_finalized = true;
_publicSwap = true;
_mintPoolShare(INIT_POOL_SUPPLY);
_pushPoolShare(msg.sender, INIT_POOL_SUPPLY);
}
function bind(address token, uint balance, uint denorm)
external
_logs_
// _lock_ Bind does not lock because it jumps to `rebind`, which does
{
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
require(!_records[token].bound, "ERR_IS_BOUND");
require(!_finalized, "ERR_IS_FINALIZED");
require(_tokens.length < MAX_BOUND_TOKENS, "ERR_MAX_TOKENS");
_records[token] = Record({
bound: true,
index: _tokens.length,
denorm: 0, // balance and denorm will be validated
balance: 0 // and set by `rebind`
});
_tokens.push(token);
rebind(token, balance, denorm);
}
function rebind(address token, uint balance, uint denorm)
public
_logs_
_lock_
{
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
require(_records[token].bound, "ERR_NOT_BOUND");
require(!_finalized, "ERR_IS_FINALIZED");
require(denorm >= MIN_WEIGHT, "ERR_MIN_WEIGHT");
require(denorm <= MAX_WEIGHT, "ERR_MAX_WEIGHT");
require(balance >= MIN_BALANCE, "ERR_MIN_BALANCE");
// Adjust the denorm and totalWeight
uint oldWeight = _records[token].denorm;
if (denorm > oldWeight) {
_totalWeight = badd(_totalWeight, bsub(denorm, oldWeight));
require(_totalWeight <= MAX_TOTAL_WEIGHT, "ERR_MAX_TOTAL_WEIGHT");
} else if (denorm < oldWeight) {
_totalWeight = bsub(_totalWeight, bsub(oldWeight, denorm));
}
_records[token].denorm = denorm;
// Adjust the balance record and actual token balance
uint oldBalance = _records[token].balance;
_records[token].balance = balance;
if (balance > oldBalance) {
_pullUnderlying(token, msg.sender, bsub(balance, oldBalance));
} else if (balance < oldBalance) {
// In this case liquidity is being withdrawn, so charge EXIT_FEE
uint tokenBalanceWithdrawn = bsub(oldBalance, balance);
uint tokenExitFee = bmul(tokenBalanceWithdrawn, EXIT_FEE);
_pushUnderlying(token, msg.sender, bsub(tokenBalanceWithdrawn, tokenExitFee));
_pushUnderlying(token, _factory, tokenExitFee);
}
}
function unbind(address token)
external
_logs_
_lock_
{
require(msg.sender == _controller, "ERR_NOT_CONTROLLER");
require(_records[token].bound, "ERR_NOT_BOUND");
require(!_finalized, "ERR_IS_FINALIZED");
uint tokenBalance = _records[token].balance;
uint tokenExitFee = bmul(tokenBalance, EXIT_FEE);
_totalWeight = bsub(_totalWeight, _records[token].denorm);
// Swap the token-to-unbind with the last token,
// then delete the last token
uint index = _records[token].index;
uint last = _tokens.length - 1;
_tokens[index] = _tokens[last];
_records[_tokens[index]].index = index;
_tokens.pop();
_records[token] = Record({
bound: false,
index: 0,
denorm: 0,
balance: 0
});
_pushUnderlying(token, msg.sender, bsub(tokenBalance, tokenExitFee));
_pushUnderlying(token, _factory, tokenExitFee);
}
// Absorb any tokens that have been sent to this contract into the pool
function gulp(address token)
external
_logs_
_lock_
{
require(_records[token].bound, "ERR_NOT_BOUND");
_records[token].balance = IERC20(token).balanceOf(address(this));
}
function getSpotPrice(address tokenIn, address tokenOut)
external view
_viewlock_
returns (uint spotPrice)
{
require(_records[tokenIn].bound, "ERR_NOT_BOUND");
require(_records[tokenOut].bound, "ERR_NOT_BOUND");
Record storage inRecord = _records[tokenIn];
Record storage outRecord = _records[tokenOut];
return calcSpotPrice(inRecord.balance, inRecord.denorm, outRecord.balance, outRecord.denorm, _swapFee);
}
function getSpotPriceSansFee(address tokenIn, address tokenOut)
external view
_viewlock_
returns (uint spotPrice)
{
require(_records[tokenIn].bound, "ERR_NOT_BOUND");
require(_records[tokenOut].bound, "ERR_NOT_BOUND");
Record storage inRecord = _records[tokenIn];
Record storage outRecord = _records[tokenOut];
return calcSpotPrice(inRecord.balance, inRecord.denorm, outRecord.balance, outRecord.denorm, 0);
}
function joinPool(uint poolAmountOut, uint[] calldata maxAmountsIn)
external
_logs_
_lock_
{
require(_finalized, "ERR_NOT_FINALIZED");
uint poolTotal = totalSupply();
uint ratio = bdiv(poolAmountOut, poolTotal);
require(ratio != 0, "ERR_MATH_APPROX");
for (uint i = 0; i < _tokens.length; i++) {
address t = _tokens[i];
uint bal = _records[t].balance;
uint tokenAmountIn = bmul(ratio, bal);
require(tokenAmountIn != 0, "ERR_MATH_APPROX");
require(tokenAmountIn <= maxAmountsIn[i], "ERR_LIMIT_IN");
_records[t].balance = badd(_records[t].balance, tokenAmountIn);
emit LOG_JOIN(msg.sender, t, tokenAmountIn);
_pullUnderlying(t, msg.sender, tokenAmountIn);
}
_mintPoolShare(poolAmountOut);
_pushPoolShare(msg.sender, poolAmountOut);
}
function exitPool(uint poolAmountIn, uint[] calldata minAmountsOut)
external
_logs_
_lock_
{
require(_finalized, "ERR_NOT_FINALIZED");
uint poolTotal = totalSupply();
uint exitFee = bmul(poolAmountIn, EXIT_FEE);
uint pAiAfterExitFee = bsub(poolAmountIn, exitFee);
uint ratio = bdiv(pAiAfterExitFee, poolTotal);
require(ratio != 0, "ERR_MATH_APPROX");
_pullPoolShare(msg.sender, poolAmountIn);
_pushPoolShare(_factory, exitFee);
_burnPoolShare(pAiAfterExitFee);
for (uint i = 0; i < _tokens.length; i++) {
address t = _tokens[i];
uint bal = _records[t].balance;
uint tokenAmountOut = bmul(ratio, bal);
require(tokenAmountOut != 0, "ERR_MATH_APPROX");
require(tokenAmountOut >= minAmountsOut[i], "ERR_LIMIT_OUT");
_records[t].balance = bsub(_records[t].balance, tokenAmountOut);
emit LOG_EXIT(msg.sender, t, tokenAmountOut);
_pushUnderlying(t, msg.sender, tokenAmountOut);
}
}
function swapExactAmountIn(
address tokenIn,
uint tokenAmountIn,
address tokenOut,
uint minAmountOut,
uint maxPrice
)
external
_logs_
_lock_
returns (uint tokenAmountOut, uint spotPriceAfter)
{
require(_records[tokenIn].bound, "ERR_NOT_BOUND");
require(_records[tokenOut].bound, "ERR_NOT_BOUND");
require(_publicSwap, "ERR_SWAP_NOT_PUBLIC");
Record storage inRecord = _records[address(tokenIn)];
Record storage outRecord = _records[address(tokenOut)];
require(tokenAmountIn <= bmul(inRecord.balance, MAX_IN_RATIO), "ERR_MAX_IN_RATIO");
uint spotPriceBefore = calcSpotPrice(
inRecord.balance,
inRecord.denorm,
outRecord.balance,
outRecord.denorm,
_swapFee
);
require(spotPriceBefore <= maxPrice, "ERR_BAD_LIMIT_PRICE");
tokenAmountOut = calcOutGivenIn(
inRecord.balance,
inRecord.denorm,
outRecord.balance,
outRecord.denorm,
tokenAmountIn,
_swapFee
);
require(tokenAmountOut >= minAmountOut, "ERR_LIMIT_OUT");
inRecord.balance = badd(inRecord.balance, tokenAmountIn);
outRecord.balance = bsub(outRecord.balance, tokenAmountOut);
spotPriceAfter = calcSpotPrice(
inRecord.balance,
inRecord.denorm,
outRecord.balance,
outRecord.denorm,
_swapFee
);
require(spotPriceAfter >= spotPriceBefore, "ERR_MATH_APPROX");
require(spotPriceAfter <= maxPrice, "ERR_LIMIT_PRICE");
require(spotPriceBefore <= bdiv(tokenAmountIn, tokenAmountOut), "ERR_MATH_APPROX");
emit LOG_SWAP(msg.sender, tokenIn, tokenOut, tokenAmountIn, tokenAmountOut);
_pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
_pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
return (tokenAmountOut, spotPriceAfter);
}
function swapExactAmountOut(
address tokenIn,
uint maxAmountIn,
address tokenOut,
uint tokenAmountOut,
uint maxPrice
)
external
_logs_
_lock_
returns (uint tokenAmountIn, uint spotPriceAfter)
{
require(_records[tokenIn].bound, "ERR_NOT_BOUND");
require(_records[tokenOut].bound, "ERR_NOT_BOUND");
require(_publicSwap, "ERR_SWAP_NOT_PUBLIC");
Record storage inRecord = _records[address(tokenIn)];
Record storage outRecord = _records[address(tokenOut)];
require(tokenAmountOut <= bmul(outRecord.balance, MAX_OUT_RATIO), "ERR_MAX_OUT_RATIO");
uint spotPriceBefore = calcSpotPrice(
inRecord.balance,
inRecord.denorm,
outRecord.balance,
outRecord.denorm,
_swapFee
);
require(spotPriceBefore <= maxPrice, "ERR_BAD_LIMIT_PRICE");
tokenAmountIn = calcInGivenOut(
inRecord.balance,
inRecord.denorm,
outRecord.balance,
outRecord.denorm,
tokenAmountOut,
_swapFee
);
require(tokenAmountIn <= maxAmountIn, "ERR_LIMIT_IN");
inRecord.balance = badd(inRecord.balance, tokenAmountIn);
outRecord.balance = bsub(outRecord.balance, tokenAmountOut);
spotPriceAfter = calcSpotPrice(
inRecord.balance,
inRecord.denorm,
outRecord.balance,
outRecord.denorm,
_swapFee
);
require(spotPriceAfter >= spotPriceBefore, "ERR_MATH_APPROX");
require(spotPriceAfter <= maxPrice, "ERR_LIMIT_PRICE");
require(spotPriceBefore <= bdiv(tokenAmountIn, tokenAmountOut), "ERR_MATH_APPROX");
emit LOG_SWAP(msg.sender, tokenIn, tokenOut, tokenAmountIn, tokenAmountOut);
_pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
_pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
return (tokenAmountIn, spotPriceAfter);
}
function joinswapExternAmountIn(address tokenIn, uint tokenAmountIn, uint minPoolAmountOut)
external
_logs_
_lock_
returns (uint poolAmountOut)
{
require(_finalized, "ERR_NOT_FINALIZED");
require(_records[tokenIn].bound, "ERR_NOT_BOUND");
require(tokenAmountIn <= bmul(_records[tokenIn].balance, MAX_IN_RATIO), "ERR_MAX_IN_RATIO");
Record storage inRecord = _records[tokenIn];
poolAmountOut = calcPoolOutGivenSingleIn(
inRecord.balance,
inRecord.denorm,
_totalSupply,
_totalWeight,
tokenAmountIn,
_swapFee
);
require(poolAmountOut >= minPoolAmountOut, "ERR_LIMIT_OUT");
inRecord.balance = badd(inRecord.balance, tokenAmountIn);
emit LOG_JOIN(msg.sender, tokenIn, tokenAmountIn);
_mintPoolShare(poolAmountOut);
_pushPoolShare(msg.sender, poolAmountOut);
_pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
return poolAmountOut;
}
function joinswapPoolAmountOut(address tokenIn, uint poolAmountOut, uint maxAmountIn)
external
_logs_
_lock_
returns (uint tokenAmountIn)
{
require(_finalized, "ERR_NOT_FINALIZED");
require(_records[tokenIn].bound, "ERR_NOT_BOUND");
Record storage inRecord = _records[tokenIn];
tokenAmountIn = calcSingleInGivenPoolOut(
inRecord.balance,
inRecord.denorm,
_totalSupply,
_totalWeight,
poolAmountOut,
_swapFee
);
require(tokenAmountIn != 0, "ERR_MATH_APPROX");
require(tokenAmountIn <= maxAmountIn, "ERR_LIMIT_IN");
require(tokenAmountIn <= bmul(_records[tokenIn].balance, MAX_IN_RATIO), "ERR_MAX_IN_RATIO");
inRecord.balance = badd(inRecord.balance, tokenAmountIn);
emit LOG_JOIN(msg.sender, tokenIn, tokenAmountIn);
_mintPoolShare(poolAmountOut);
_pushPoolShare(msg.sender, poolAmountOut);
_pullUnderlying(tokenIn, msg.sender, tokenAmountIn);
return tokenAmountIn;
}
function exitswapPoolAmountIn(address tokenOut, uint poolAmountIn, uint minAmountOut)
external
_logs_
_lock_
returns (uint tokenAmountOut)
{
require(_finalized, "ERR_NOT_FINALIZED");
require(_records[tokenOut].bound, "ERR_NOT_BOUND");
Record storage outRecord = _records[tokenOut];
tokenAmountOut = calcSingleOutGivenPoolIn(
outRecord.balance,
outRecord.denorm,
_totalSupply,
_totalWeight,
poolAmountIn,
_swapFee
);
require(tokenAmountOut >= minAmountOut, "ERR_LIMIT_OUT");
require(tokenAmountOut <= bmul(_records[tokenOut].balance, MAX_OUT_RATIO), "ERR_MAX_OUT_RATIO");
outRecord.balance = bsub(outRecord.balance, tokenAmountOut);
uint exitFee = bmul(poolAmountIn, EXIT_FEE);
emit LOG_EXIT(msg.sender, tokenOut, tokenAmountOut);
_pullPoolShare(msg.sender, poolAmountIn);
_burnPoolShare(bsub(poolAmountIn, exitFee));
_pushPoolShare(_factory, exitFee);
_pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
return tokenAmountOut;
}
function exitswapExternAmountOut(address tokenOut, uint tokenAmountOut, uint maxPoolAmountIn)
external
_logs_
_lock_
returns (uint poolAmountIn)
{
require(_finalized, "ERR_NOT_FINALIZED");
require(_records[tokenOut].bound, "ERR_NOT_BOUND");
require(tokenAmountOut <= bmul(_records[tokenOut].balance, MAX_OUT_RATIO), "ERR_MAX_OUT_RATIO");
Record storage outRecord = _records[tokenOut];
poolAmountIn = calcPoolInGivenSingleOut(
outRecord.balance,
outRecord.denorm,
_totalSupply,
_totalWeight,
tokenAmountOut,
_swapFee
);
require(poolAmountIn != 0, "ERR_MATH_APPROX");
require(poolAmountIn <= maxPoolAmountIn, "ERR_LIMIT_IN");
outRecord.balance = bsub(outRecord.balance, tokenAmountOut);
uint exitFee = bmul(poolAmountIn, EXIT_FEE);
emit LOG_EXIT(msg.sender, tokenOut, tokenAmountOut);
_pullPoolShare(msg.sender, poolAmountIn);
_burnPoolShare(bsub(poolAmountIn, exitFee));
_pushPoolShare(_factory, exitFee);
_pushUnderlying(tokenOut, msg.sender, tokenAmountOut);
return poolAmountIn;
}
// ==
// 'Underlying' token-manipulation functions make external calls but are NOT locked
// You must `_lock_` or otherwise ensure reentry-safety
function _pullUnderlying(address erc20, address from, uint amount)
internal
{
bool xfer = IERC20(erc20).transferFrom(from, address(this), amount);
require(xfer, "ERR_ERC20_FALSE");
}
function _pushUnderlying(address erc20, address to, uint amount)
internal
{
bool xfer = IERC20(erc20).transfer(to, amount);
require(xfer, "ERR_ERC20_FALSE");
}
function _pullPoolShare(address from, uint amount)
internal
{
_pull(from, amount);
}
function _pushPoolShare(address to, uint amount)
internal
{
_push(to, amount);
}
function _mintPoolShare(uint amount)
internal
{
_mint(amount);
}
function _burnPoolShare(uint amount)
internal
{
_burn(amount);
}
}
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
pragma solidity 0.5.12;
import "./BNum.sol";
// Highly opinionated token implementation
interface IERC20 {
event Approval(address indexed src, address indexed dst, uint amt);
event Transfer(address indexed src, address indexed dst, uint amt);
function totalSupply() external view returns (uint);
function balanceOf(address whom) external view returns (uint);
function allowance(address src, address dst) external view returns (uint);
function approve(address dst, uint amt) external returns (bool);
function transfer(address dst, uint amt) external returns (bool);
function transferFrom(
address src, address dst, uint amt
) external returns (bool);
}
contract BTokenBase is BNum {
mapping(address => uint) internal _balance;
mapping(address => mapping(address=>uint)) internal _allowance;
uint internal _totalSupply;
event Approval(address indexed src, address indexed dst, uint amt);
event Transfer(address indexed src, address indexed dst, uint amt);
function _mint(uint amt) internal {
_balance[address(this)] = badd(_balance[address(this)], amt);
_totalSupply = badd(_totalSupply, amt);
emit Transfer(address(0), address(this), amt);
}
function _burn(uint amt) internal {
require(_balance[address(this)] >= amt, "ERR_INSUFFICIENT_BAL");
_balance[address(this)] = bsub(_balance[address(this)], amt);
_totalSupply = bsub(_totalSupply, amt);
emit Transfer(address(this), address(0), amt);
}
function _move(address src, address dst, uint amt) internal {
require(_balance[src] >= amt, "ERR_INSUFFICIENT_BAL");
_balance[src] = bsub(_balance[src], amt);
_balance[dst] = badd(_balance[dst], amt);
emit Transfer(src, dst, amt);
}
function _push(address to, uint amt) internal {
_move(address(this), to, amt);
}
function _pull(address from, uint amt) internal {
_move(from, address(this), amt);
}
}
contract BToken is BTokenBase, IERC20 {
string private _name = "Balancer Pool Token";
string private _symbol = "BPT";
uint8 private _decimals = 18;
function name() public view returns (string memory) {
return _name;
}
function symbol() public view returns (string memory) {
return _symbol;
}
function decimals() public view returns(uint8) {
return _decimals;
}
function allowance(address src, address dst) external view returns (uint) {
return _allowance[src][dst];
}
function balanceOf(address whom) external view returns (uint) {
return _balance[whom];
}
function totalSupply() public view returns (uint) {
return _totalSupply;
}
function approve(address dst, uint amt) external returns (bool) {
_allowance[msg.sender][dst] = amt;
emit Approval(msg.sender, dst, amt);
return true;
}
function increaseApproval(address dst, uint amt) external returns (bool) {
_allowance[msg.sender][dst] = badd(_allowance[msg.sender][dst], amt);
emit Approval(msg.sender, dst, _allowance[msg.sender][dst]);
return true;
}
function decreaseApproval(address dst, uint amt) external returns (bool) {
uint oldValue = _allowance[msg.sender][dst];
if (amt > oldValue) {
_allowance[msg.sender][dst] = 0;
} else {
_allowance[msg.sender][dst] = bsub(oldValue, amt);
}
emit Approval(msg.sender, dst, _allowance[msg.sender][dst]);
return true;
}
function transfer(address dst, uint amt) external returns (bool) {
_move(msg.sender, dst, amt);
return true;
}
function transferFrom(address src, address dst, uint amt) external returns (bool) {
require(msg.sender == src || amt <= _allowance[src][msg.sender], "ERR_BTOKEN_BAD_CALLER");
_move(src, dst, amt);
if (msg.sender != src && _allowance[src][msg.sender] != uint256(-1)) {
_allowance[src][msg.sender] = bsub(_allowance[src][msg.sender], amt);
emit Approval(msg.sender, dst, _allowance[src][msg.sender]);
}
return true;
}
}
