Transaction Decoder

pragma solidity 0.5.12;

contract FileLike {
    function file(bytes32, uint256) external;
    function file(bytes32, bytes32, uint256) external;
}

contract JugLike {
    function drip(bytes32) external;
    function file(bytes32, bytes32, uint256) external;
}

contract PotLike {
    function drip() external;
    function file(bytes32, uint256) external;
}

contract PauseLike {
    function delay() external view returns (uint256);
    function plot(address, bytes32, bytes calldata, uint256) external;
    function exec(address, bytes32, bytes calldata, uint256) external;
}

contract MomLike {
    function setCap(uint256) external;
    function setFee(uint256) external;
}

contract DssFlopReplaceSpellAction {
    uint256 constant RAD = 10 ** 45;
    address constant public VAT = 0x35D1b3F3D7966A1DFe207aa4514C12a259A0492B;
    address constant public JUG = 0x19c0976f590D67707E62397C87829d896Dc0f1F1;
    address constant public POT = 0x197E90f9FAD81970bA7976f33CbD77088E5D7cf7;

    function execute() external {
        // set the global debt ceiling to 178,000,000
        FileLike(VAT).file("Line", 178000000 * RAD);

        // set the ETH-A debt ceiling to 75,000,000
        FileLike(VAT).file("ETH-A", "line", 75000000 * RAD);

        // DSR
        PotLike(POT).drip();
        PotLike(POT).file("dsr", 1000000001243680656318820312);

        // drip
        // JugLike(JUG).drip("ETH-A");
        // JugLike(JUG).drip("BAT-A");

        // set ETH-A duty to X
        // JugLike(JUG).file("ETH-A", "duty", X);

        // set BAT-A duty to X
        // JugLike(JUG).file("BAT-A", "duty", X);
    }
}

contract DssDecember6Spell {
    PauseLike public pause =
        PauseLike(0xbE286431454714F511008713973d3B053A2d38f3);
    address constant public SAIMOM = 0xF2C5369cFFb8Ea6284452b0326e326DbFdCb867C;
    uint256 constant public SCDCAP = 95000000 * 10 ** 18;
    uint256 constant public NEWFEE = 1000000000937303470807876289;
    address   public action;
    bytes32   public tag;
    uint256   public eta;
    bytes     public sig;
    bool      public done;

    constructor() public {
        sig = abi.encodeWithSignature("execute()");
        action = address(new DssFlopReplaceSpellAction());
        bytes32 _tag;
        address _action = action;
        assembly { _tag := extcodehash(_action) }
        tag = _tag;
    }

    function cast() external {
        require(!done, "spell-already-cast");
        done = true;
        pause.plot(action, tag, sig, now);
        pause.exec(action, tag, sig, now);
        // Lower Debt Ceiling in SCD to 95,000,000
        MomLike(SAIMOM).setCap(SCDCAP);
        MomLike(SAIMOM).setFee(NEWFEE);
    }
}

// hevm: flattened sources of /nix/store/b2bvh9ljr3yljrdz6lm764hdyj7nk4iy-ds-pause-f43edc1/src/pause.sol
pragma solidity >=0.4.23 >=0.5.0 <0.6.0;

////// /nix/store/6qq1ps6wrikrl6ha3q33739dbs2wg2hb-ds-note/dapp/ds-note/src/note.sol
/// note.sol -- the `note' modifier, for logging calls as events

// 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 >=0.4.23; */

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint256           wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;
        uint256 wad;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
            wad := callvalue
        }

        emit LogNote(msg.sig, msg.sender, foo, bar, wad, msg.data);

        _;
    }
}

////// /nix/store/r1w3fgb8wh0c2qn0i8jg95sv99l5nh7j-ds-auth/dapp/ds-auth/src/auth.sol
// 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 >=0.4.23; */

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    constructor() public {
        owner = msg.sender;
        emit LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        emit LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig), "ds-auth-unauthorized");
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, address(this), sig);
        }
    }
}

////// /nix/store/b2bvh9ljr3yljrdz6lm764hdyj7nk4iy-ds-pause-f43edc1/src/pause.sol
// Copyright (C) 2019 David Terry <[email protected]>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

/* pragma solidity >=0.5.0 <0.6.0; */

/* import {DSNote} from "ds-note/note.sol"; */
/* import {DSAuth, DSAuthority} from "ds-auth/auth.sol"; */

contract DSPause is DSAuth, DSNote {

    // --- admin ---

    modifier wait { require(msg.sender == address(proxy), "ds-pause-undelayed-call"); _; }

    function setOwner(address owner_) public wait {
        owner = owner_;
        emit LogSetOwner(owner);
    }
    function setAuthority(DSAuthority authority_) public wait {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }
    function setDelay(uint delay_) public note wait {
        delay = delay_;
    }

    // --- math ---

    function add(uint x, uint y) internal pure returns (uint z) {
        z = x + y;
        require(z >= x, "ds-pause-addition-overflow");
    }

    // --- data ---

    mapping (bytes32 => bool) public plans;
    DSPauseProxy public proxy;
    uint         public delay;

    // --- init ---

    constructor(uint delay_, address owner_, DSAuthority authority_) public {
        delay = delay_;
        owner = owner_;
        authority = authority_;
        proxy = new DSPauseProxy();
    }

    // --- util ---

    function hash(address usr, bytes32 tag, bytes memory fax, uint eta)
        internal pure
        returns (bytes32)
    {
        return keccak256(abi.encode(usr, tag, fax, eta));
    }

    function soul(address usr)
        internal view
        returns (bytes32 tag)
    {
        assembly { tag := extcodehash(usr) }
    }

    // --- operations ---

    function plot(address usr, bytes32 tag, bytes memory fax, uint eta)
        public note auth
    {
        require(eta >= add(now, delay), "ds-pause-delay-not-respected");
        plans[hash(usr, tag, fax, eta)] = true;
    }

    function drop(address usr, bytes32 tag, bytes memory fax, uint eta)
        public note auth
    {
        plans[hash(usr, tag, fax, eta)] = false;
    }

    function exec(address usr, bytes32 tag, bytes memory fax, uint eta)
        public note
        returns (bytes memory out)
    {
        require(plans[hash(usr, tag, fax, eta)], "ds-pause-unplotted-plan");
        require(soul(usr) == tag,                "ds-pause-wrong-codehash");
        require(now >= eta,                      "ds-pause-premature-exec");

        plans[hash(usr, tag, fax, eta)] = false;

        out = proxy.exec(usr, fax);
        require(proxy.owner() == address(this), "ds-pause-illegal-storage-change");
    }
}

// plans are executed in an isolated storage context to protect the pause from
// malicious storage modification during plan execution
contract DSPauseProxy {
    address public owner;
    modifier auth { require(msg.sender == owner, "ds-pause-proxy-unauthorized"); _; }
    constructor() public { owner = msg.sender; }

    function exec(address usr, bytes memory fax)
        public auth
        returns (bytes memory out)
    {
        bool ok;
        (ok, out) = usr.delegatecall(fax);
        require(ok, "ds-pause-delegatecall-error");
    }
}

// hevm: flattened sources of /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/vat.sol
pragma solidity =0.5.12;

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/vat.sol
/// vat.sol -- Dai CDP database

// Copyright (C) 2018 Rain <[email protected]>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

/* pragma solidity 0.5.12; */

contract Vat {
    // --- Auth ---
    mapping (address => uint) public wards;
    function rely(address usr) external note auth { require(live == 1, "Vat/not-live"); wards[usr] = 1; }
    function deny(address usr) external note auth { require(live == 1, "Vat/not-live"); wards[usr] = 0; }
    modifier auth {
        require(wards[msg.sender] == 1, "Vat/not-authorized");
        _;
    }

    mapping(address => mapping (address => uint)) public can;
    function hope(address usr) external note { can[msg.sender][usr] = 1; }
    function nope(address usr) external note { can[msg.sender][usr] = 0; }
    function wish(address bit, address usr) internal view returns (bool) {
        return either(bit == usr, can[bit][usr] == 1);
    }

    // --- Data ---
    struct Ilk {
        uint256 Art;   // Total Normalised Debt     [wad]
        uint256 rate;  // Accumulated Rates         [ray]
        uint256 spot;  // Price with Safety Margin  [ray]
        uint256 line;  // Debt Ceiling              [rad]
        uint256 dust;  // Urn Debt Floor            [rad]
    }
    struct Urn {
        uint256 ink;   // Locked Collateral  [wad]
        uint256 art;   // Normalised Debt    [wad]
    }

    mapping (bytes32 => Ilk)                       public ilks;
    mapping (bytes32 => mapping (address => Urn )) public urns;
    mapping (bytes32 => mapping (address => uint)) public gem;  // [wad]
    mapping (address => uint256)                   public dai;  // [rad]
    mapping (address => uint256)                   public sin;  // [rad]

    uint256 public debt;  // Total Dai Issued    [rad]
    uint256 public vice;  // Total Unbacked Dai  [rad]
    uint256 public Line;  // Total Debt Ceiling  [rad]
    uint256 public live;  // Access Flag

    // --- Logs ---
    event LogNote(
        bytes4   indexed  sig,
        bytes32  indexed  arg1,
        bytes32  indexed  arg2,
        bytes32  indexed  arg3,
        bytes             data
    ) anonymous;

    modifier note {
        _;
        assembly {
            // log an 'anonymous' event with a constant 6 words of calldata
            // and four indexed topics: the selector and the first three args
            let mark := msize                         // end of memory ensures zero
            mstore(0x40, add(mark, 288))              // update free memory pointer
            mstore(mark, 0x20)                        // bytes type data offset
            mstore(add(mark, 0x20), 224)              // bytes size (padded)
            calldatacopy(add(mark, 0x40), 0, 224)     // bytes payload
            log4(mark, 288,                           // calldata
                 shl(224, shr(224, calldataload(0))), // msg.sig
                 calldataload(4),                     // arg1
                 calldataload(36),                    // arg2
                 calldataload(68)                     // arg3
                )
        }
    }

    // --- Init ---
    constructor() public {
        wards[msg.sender] = 1;
        live = 1;
    }

    // --- Math ---
    function add(uint x, int y) internal pure returns (uint z) {
        z = x + uint(y);
        require(y >= 0 || z <= x);
        require(y <= 0 || z >= x);
    }
    function sub(uint x, int y) internal pure returns (uint z) {
        z = x - uint(y);
        require(y <= 0 || z <= x);
        require(y >= 0 || z >= x);
    }
    function mul(uint x, int y) internal pure returns (int z) {
        z = int(x) * y;
        require(int(x) >= 0);
        require(y == 0 || z / y == int(x));
    }
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x);
    }

    // --- Administration ---
    function init(bytes32 ilk) external note auth {
        require(ilks[ilk].rate == 0, "Vat/ilk-already-init");
        ilks[ilk].rate = 10 ** 27;
    }
    function file(bytes32 what, uint data) external note auth {
        require(live == 1, "Vat/not-live");
        if (what == "Line") Line = data;
        else revert("Vat/file-unrecognized-param");
    }
    function file(bytes32 ilk, bytes32 what, uint data) external note auth {
        require(live == 1, "Vat/not-live");
        if (what == "spot") ilks[ilk].spot = data;
        else if (what == "line") ilks[ilk].line = data;
        else if (what == "dust") ilks[ilk].dust = data;
        else revert("Vat/file-unrecognized-param");
    }
    function cage() external note auth {
        live = 0;
    }

    // --- Fungibility ---
    function slip(bytes32 ilk, address usr, int256 wad) external note auth {
        gem[ilk][usr] = add(gem[ilk][usr], wad);
    }
    function flux(bytes32 ilk, address src, address dst, uint256 wad) external note {
        require(wish(src, msg.sender), "Vat/not-allowed");
        gem[ilk][src] = sub(gem[ilk][src], wad);
        gem[ilk][dst] = add(gem[ilk][dst], wad);
    }
    function move(address src, address dst, uint256 rad) external note {
        require(wish(src, msg.sender), "Vat/not-allowed");
        dai[src] = sub(dai[src], rad);
        dai[dst] = add(dai[dst], rad);
    }

    function either(bool x, bool y) internal pure returns (bool z) {
        assembly{ z := or(x, y)}
    }
    function both(bool x, bool y) internal pure returns (bool z) {
        assembly{ z := and(x, y)}
    }

    // --- CDP Manipulation ---
    function frob(bytes32 i, address u, address v, address w, int dink, int dart) external note {
        // system is live
        require(live == 1, "Vat/not-live");

        Urn memory urn = urns[i][u];
        Ilk memory ilk = ilks[i];
        // ilk has been initialised
        require(ilk.rate != 0, "Vat/ilk-not-init");

        urn.ink = add(urn.ink, dink);
        urn.art = add(urn.art, dart);
        ilk.Art = add(ilk.Art, dart);

        int dtab = mul(ilk.rate, dart);
        uint tab = mul(ilk.rate, urn.art);
        debt     = add(debt, dtab);

        // either debt has decreased, or debt ceilings are not exceeded
        require(either(dart <= 0, both(mul(ilk.Art, ilk.rate) <= ilk.line, debt <= Line)), "Vat/ceiling-exceeded");
        // urn is either less risky than before, or it is safe
        require(either(both(dart <= 0, dink >= 0), tab <= mul(urn.ink, ilk.spot)), "Vat/not-safe");

        // urn is either more safe, or the owner consents
        require(either(both(dart <= 0, dink >= 0), wish(u, msg.sender)), "Vat/not-allowed-u");
        // collateral src consents
        require(either(dink <= 0, wish(v, msg.sender)), "Vat/not-allowed-v");
        // debt dst consents
        require(either(dart >= 0, wish(w, msg.sender)), "Vat/not-allowed-w");

        // urn has no debt, or a non-dusty amount
        require(either(urn.art == 0, tab >= ilk.dust), "Vat/dust");

        gem[i][v] = sub(gem[i][v], dink);
        dai[w]    = add(dai[w],    dtab);

        urns[i][u] = urn;
        ilks[i]    = ilk;
    }
    // --- CDP Fungibility ---
    function fork(bytes32 ilk, address src, address dst, int dink, int dart) external note {
        Urn storage u = urns[ilk][src];
        Urn storage v = urns[ilk][dst];
        Ilk storage i = ilks[ilk];

        u.ink = sub(u.ink, dink);
        u.art = sub(u.art, dart);
        v.ink = add(v.ink, dink);
        v.art = add(v.art, dart);

        uint utab = mul(u.art, i.rate);
        uint vtab = mul(v.art, i.rate);

        // both sides consent
        require(both(wish(src, msg.sender), wish(dst, msg.sender)), "Vat/not-allowed");

        // both sides safe
        require(utab <= mul(u.ink, i.spot), "Vat/not-safe-src");
        require(vtab <= mul(v.ink, i.spot), "Vat/not-safe-dst");

        // both sides non-dusty
        require(either(utab >= i.dust, u.art == 0), "Vat/dust-src");
        require(either(vtab >= i.dust, v.art == 0), "Vat/dust-dst");
    }
    // --- CDP Confiscation ---
    function grab(bytes32 i, address u, address v, address w, int dink, int dart) external note auth {
        Urn storage urn = urns[i][u];
        Ilk storage ilk = ilks[i];

        urn.ink = add(urn.ink, dink);
        urn.art = add(urn.art, dart);
        ilk.Art = add(ilk.Art, dart);

        int dtab = mul(ilk.rate, dart);

        gem[i][v] = sub(gem[i][v], dink);
        sin[w]    = sub(sin[w],    dtab);
        vice      = sub(vice,      dtab);
    }

    // --- Settlement ---
    function heal(uint rad) external note {
        address u = msg.sender;
        sin[u] = sub(sin[u], rad);
        dai[u] = sub(dai[u], rad);
        vice   = sub(vice,   rad);
        debt   = sub(debt,   rad);
    }
    function suck(address u, address v, uint rad) external note auth {
        sin[u] = add(sin[u], rad);
        dai[v] = add(dai[v], rad);
        vice   = add(vice,   rad);
        debt   = add(debt,   rad);
    }

    // --- Rates ---
    function fold(bytes32 i, address u, int rate) external note auth {
        require(live == 1, "Vat/not-live");
        Ilk storage ilk = ilks[i];
        ilk.rate = add(ilk.rate, rate);
        int rad  = mul(ilk.Art, rate);
        dai[u]   = add(dai[u], rad);
        debt     = add(debt,   rad);
    }
}

// hevm: flattened sources of /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/pot.sol
pragma solidity =0.5.12;

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/lib.sol
// 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 LibNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  usr,
        bytes32  indexed  arg1,
        bytes32  indexed  arg2,
        bytes             data
    ) anonymous;

    modifier note {
        _;
        assembly {
            // log an 'anonymous' event with a constant 6 words of calldata
            // and four indexed topics: selector, caller, arg1 and arg2
            let mark := msize                         // end of memory ensures zero
            mstore(0x40, add(mark, 288))              // update free memory pointer
            mstore(mark, 0x20)                        // bytes type data offset
            mstore(add(mark, 0x20), 224)              // bytes size (padded)
            calldatacopy(add(mark, 0x40), 0, 224)     // bytes payload
            log4(mark, 288,                           // calldata
                 shl(224, shr(224, calldataload(0))), // msg.sig
                 caller,                              // msg.sender
                 calldataload(4),                     // arg1
                 calldataload(36)                     // arg2
                )
        }
    }
}

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/pot.sol
/// pot.sol -- Dai Savings Rate

// Copyright (C) 2018 Rain <[email protected]>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

/* pragma solidity 0.5.12; */

/* import "./lib.sol"; */

/*
   "Savings Dai" is obtained when Dai is deposited into
   this contract. Each "Savings Dai" accrues Dai interest
   at the "Dai Savings Rate".

   This contract does not implement a user tradeable token
   and is intended to be used with adapters.

         --- `save` your `dai` in the `pot` ---

   - `dsr`: the Dai Savings Rate
   - `pie`: user balance of Savings Dai

   - `join`: start saving some dai
   - `exit`: remove some dai
   - `drip`: perform rate collection

*/

contract VatLike {
    function move(address,address,uint256) external;
    function suck(address,address,uint256) external;
}

contract Pot is LibNote {
    // --- Auth ---
    mapping (address => uint) public wards;
    function rely(address guy) external note auth { wards[guy] = 1; }
    function deny(address guy) external note auth { wards[guy] = 0; }
    modifier auth {
        require(wards[msg.sender] == 1, "Pot/not-authorized");
        _;
    }

    // --- Data ---
    mapping (address => uint256) public pie;  // user Savings Dai

    uint256 public Pie;  // total Savings Dai
    uint256 public dsr;  // the Dai Savings Rate
    uint256 public chi;  // the Rate Accumulator

    VatLike public vat;  // CDP engine
    address public vow;  // debt engine
    uint256 public rho;  // time of last drip

    uint256 public live;  // Access Flag

    // --- Init ---
    constructor(address vat_) public {
        wards[msg.sender] = 1;
        vat = VatLike(vat_);
        dsr = ONE;
        chi = ONE;
        rho = now;
        live = 1;
    }

    // --- Math ---
    uint256 constant ONE = 10 ** 27;
    function rpow(uint x, uint n, uint base) internal pure returns (uint z) {
        assembly {
            switch x case 0 {switch n case 0 {z := base} default {z := 0}}
            default {
                switch mod(n, 2) case 0 { z := base } default { z := x }
                let half := div(base, 2)  // for rounding.
                for { n := div(n, 2) } n { n := div(n,2) } {
                    let xx := mul(x, x)
                    if iszero(eq(div(xx, x), x)) { revert(0,0) }
                    let xxRound := add(xx, half)
                    if lt(xxRound, xx) { revert(0,0) }
                    x := div(xxRound, base)
                    if mod(n,2) {
                        let zx := mul(z, x)
                        if and(iszero(iszero(x)), iszero(eq(div(zx, x), z))) { revert(0,0) }
                        let zxRound := add(zx, half)
                        if lt(zxRound, zx) { revert(0,0) }
                        z := div(zxRound, base)
                    }
                }
            }
        }
    }

    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = mul(x, y) / ONE;
    }

    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }

    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }

    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x);
    }

    // --- Administration ---
    function file(bytes32 what, uint256 data) external note auth {
        require(live == 1, "Pot/not-live");
        require(now == rho, "Pot/rho-not-updated");
        if (what == "dsr") dsr = data;
        else revert("Pot/file-unrecognized-param");
    }

    function file(bytes32 what, address addr) external note auth {
        if (what == "vow") vow = addr;
        else revert("Pot/file-unrecognized-param");
    }

    function cage() external note auth {
        live = 0;
        dsr = ONE;
    }

    // --- Savings Rate Accumulation ---
    function drip() external note returns (uint tmp) {
        require(now >= rho, "Pot/invalid-now");
        tmp = rmul(rpow(dsr, now - rho, ONE), chi);
        uint chi_ = sub(tmp, chi);
        chi = tmp;
        rho = now;
        vat.suck(address(vow), address(this), mul(Pie, chi_));
    }

    // --- Savings Dai Management ---
    function join(uint wad) external note {
        require(now == rho, "Pot/rho-not-updated");
        pie[msg.sender] = add(pie[msg.sender], wad);
        Pie             = add(Pie,             wad);
        vat.move(msg.sender, address(this), mul(chi, wad));
    }

    function exit(uint wad) external note {
        pie[msg.sender] = sub(pie[msg.sender], wad);
        Pie             = sub(Pie,             wad);
        vat.move(address(this), msg.sender, mul(chi, wad));
    }
}

// hevm: flattened sources of src/mom.sol
pragma solidity ^0.4.18;

////// lib/ds-guard/lib/ds-auth/src/auth.sol
// 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 ^0.4.13; */

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    function DSAuth() public {
        owner = msg.sender;
        LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        LogSetAuthority(authority);
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig));
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, this, sig);
        }
    }
}

////// lib/ds-spell/lib/ds-note/src/note.sol
/// note.sol -- the `note' modifier, for logging calls as events

// 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 ^0.4.13; */

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint              wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
        }

        LogNote(msg.sig, msg.sender, foo, bar, msg.value, msg.data);

        _;
    }
}

////// lib/ds-thing/lib/ds-math/src/math.sol
/// math.sol -- mixin for inline numerical wizardry

// 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 ^0.4.13; */

contract DSMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x);
    }

    function min(uint x, uint y) internal pure returns (uint z) {
        return x <= y ? x : y;
    }
    function max(uint x, uint y) internal pure returns (uint z) {
        return x >= y ? x : y;
    }
    function imin(int x, int y) internal pure returns (int z) {
        return x <= y ? x : y;
    }
    function imax(int x, int y) internal pure returns (int z) {
        return x >= y ? x : y;
    }

    uint constant WAD = 10 ** 18;
    uint constant RAY = 10 ** 27;

    function wmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), WAD / 2) / WAD;
    }
    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), RAY / 2) / RAY;
    }
    function wdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, WAD), y / 2) / y;
    }
    function rdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, RAY), y / 2) / y;
    }

    // This famous algorithm is called "exponentiation by squaring"
    // and calculates x^n with x as fixed-point and n as regular unsigned.
    //
    // It's O(log n), instead of O(n) for naive repeated multiplication.
    //
    // These facts are why it works:
    //
    //  If n is even, then x^n = (x^2)^(n/2).
    //  If n is odd,  then x^n = x * x^(n-1),
    //   and applying the equation for even x gives
    //    x^n = x * (x^2)^((n-1) / 2).
    //
    //  Also, EVM division is flooring and
    //    floor[(n-1) / 2] = floor[n / 2].
    //
    function rpow(uint x, uint n) internal pure returns (uint z) {
        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }
}

////// lib/ds-thing/src/thing.sol
// thing.sol - `auth` with handy mixins. your things should be DSThings

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import 'ds-auth/auth.sol'; */
/* import 'ds-note/note.sol'; */
/* import 'ds-math/math.sol'; */

contract DSThing is DSAuth, DSNote, DSMath {

    function S(string s) internal pure returns (bytes4) {
        return bytes4(keccak256(s));
    }

}

////// lib/ds-token/lib/ds-stop/src/stop.sol
/// stop.sol -- mixin for enable/disable functionality

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "ds-auth/auth.sol"; */
/* import "ds-note/note.sol"; */

contract DSStop is DSNote, DSAuth {

    bool public stopped;

    modifier stoppable {
        require(!stopped);
        _;
    }
    function stop() public auth note {
        stopped = true;
    }
    function start() public auth note {
        stopped = false;
    }

}

////// lib/ds-token/lib/erc20/src/erc20.sol
/// erc20.sol -- API for the ERC20 token standard

// See <https://github.com/ethereum/EIPs/issues/20>.

// This file likely does not meet the threshold of originality
// required for copyright to apply.  As a result, this is free and
// unencumbered software belonging to the public domain.

/* pragma solidity ^0.4.8; */

contract ERC20Events {
    event Approval(address indexed src, address indexed guy, uint wad);
    event Transfer(address indexed src, address indexed dst, uint wad);
}

contract ERC20 is ERC20Events {
    function totalSupply() public view returns (uint);
    function balanceOf(address guy) public view returns (uint);
    function allowance(address src, address guy) public view returns (uint);

    function approve(address guy, uint wad) public returns (bool);
    function transfer(address dst, uint wad) public returns (bool);
    function transferFrom(
        address src, address dst, uint wad
    ) public returns (bool);
}

////// lib/ds-token/src/base.sol
/// base.sol -- basic ERC20 implementation

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "erc20/erc20.sol"; */
/* import "ds-math/math.sol"; */

contract DSTokenBase is ERC20, DSMath {
    uint256                                            _supply;
    mapping (address => uint256)                       _balances;
    mapping (address => mapping (address => uint256))  _approvals;

    function DSTokenBase(uint supply) public {
        _balances[msg.sender] = supply;
        _supply = supply;
    }

    function totalSupply() public view returns (uint) {
        return _supply;
    }
    function balanceOf(address src) public view returns (uint) {
        return _balances[src];
    }
    function allowance(address src, address guy) public view returns (uint) {
        return _approvals[src][guy];
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        if (src != msg.sender) {
            _approvals[src][msg.sender] = sub(_approvals[src][msg.sender], wad);
        }

        _balances[src] = sub(_balances[src], wad);
        _balances[dst] = add(_balances[dst], wad);

        Transfer(src, dst, wad);

        return true;
    }

    function approve(address guy, uint wad) public returns (bool) {
        _approvals[msg.sender][guy] = wad;

        Approval(msg.sender, guy, wad);

        return true;
    }
}

////// lib/ds-token/src/token.sol
/// token.sol -- ERC20 implementation with minting and burning

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "ds-stop/stop.sol"; */

/* import "./base.sol"; */

contract DSToken is DSTokenBase(0), DSStop {

    bytes32  public  symbol;
    uint256  public  decimals = 18; // standard token precision. override to customize

    function DSToken(bytes32 symbol_) public {
        symbol = symbol_;
    }

    event Mint(address indexed guy, uint wad);
    event Burn(address indexed guy, uint wad);

    function approve(address guy) public stoppable returns (bool) {
        return super.approve(guy, uint(-1));
    }

    function approve(address guy, uint wad) public stoppable returns (bool) {
        return super.approve(guy, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        stoppable
        returns (bool)
    {
        if (src != msg.sender && _approvals[src][msg.sender] != uint(-1)) {
            _approvals[src][msg.sender] = sub(_approvals[src][msg.sender], wad);
        }

        _balances[src] = sub(_balances[src], wad);
        _balances[dst] = add(_balances[dst], wad);

        Transfer(src, dst, wad);

        return true;
    }

    function push(address dst, uint wad) public {
        transferFrom(msg.sender, dst, wad);
    }
    function pull(address src, uint wad) public {
        transferFrom(src, msg.sender, wad);
    }
    function move(address src, address dst, uint wad) public {
        transferFrom(src, dst, wad);
    }

    function mint(uint wad) public {
        mint(msg.sender, wad);
    }
    function burn(uint wad) public {
        burn(msg.sender, wad);
    }
    function mint(address guy, uint wad) public auth stoppable {
        _balances[guy] = add(_balances[guy], wad);
        _supply = add(_supply, wad);
        Mint(guy, wad);
    }
    function burn(address guy, uint wad) public auth stoppable {
        if (guy != msg.sender && _approvals[guy][msg.sender] != uint(-1)) {
            _approvals[guy][msg.sender] = sub(_approvals[guy][msg.sender], wad);
        }

        _balances[guy] = sub(_balances[guy], wad);
        _supply = sub(_supply, wad);
        Burn(guy, wad);
    }

    // Optional token name
    bytes32   public  name = "";

    function setName(bytes32 name_) public auth {
        name = name_;
    }
}

////// lib/ds-value/src/value.sol
/// value.sol - a value is a simple thing, it can be get and set

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import 'ds-thing/thing.sol'; */

contract DSValue is DSThing {
    bool    has;
    bytes32 val;
    function peek() public view returns (bytes32, bool) {
        return (val,has);
    }
    function read() public view returns (bytes32) {
        var (wut, haz) = peek();
        assert(haz);
        return wut;
    }
    function poke(bytes32 wut) public note auth {
        val = wut;
        has = true;
    }
    function void() public note auth {  // unset the value
        has = false;
    }
}

////// src/vox.sol
/// vox.sol -- target price feed

// Copyright (C) 2016, 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2016, 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017        Rain Break <[email protected]>

// 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 ^0.4.18; */

/* import "ds-thing/thing.sol"; */

contract SaiVox is DSThing {
    uint256  _par;
    uint256  _way;

    uint256  public  fix;
    uint256  public  how;
    uint256  public  tau;

    function SaiVox(uint par_) public {
        _par = fix = par_;
        _way = RAY;
        tau  = era();
    }

    function era() public view returns (uint) {
        return block.timestamp;
    }

    function mold(bytes32 param, uint val) public note auth {
        if (param == 'way') _way = val;
    }

    // Dai Target Price (ref per dai)
    function par() public returns (uint) {
        prod();
        return _par;
    }
    function way() public returns (uint) {
        prod();
        return _way;
    }

    function tell(uint256 ray) public note auth {
        fix = ray;
    }
    function tune(uint256 ray) public note auth {
        how = ray;
    }

    function prod() public note {
        var age = era() - tau;
        if (age == 0) return;  // optimised
        tau = era();

        if (_way != RAY) _par = rmul(_par, rpow(_way, age));  // optimised

        if (how == 0) return;  // optimised
        var wag = int128(how * age);
        _way = inj(prj(_way) + (fix < _par ? wag : -wag));
    }

    function inj(int128 x) internal pure returns (uint256) {
        return x >= 0 ? uint256(x) + RAY
            : rdiv(RAY, RAY + uint256(-x));
    }
    function prj(uint256 x) internal pure returns (int128) {
        return x >= RAY ? int128(x - RAY)
            : int128(RAY) - int128(rdiv(RAY, x));
    }
}

////// src/tub.sol
/// tub.sol -- simplified CDP engine (baby brother of `vat')

// Copyright (C) 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017  Rain Break <[email protected]>

// 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 ^0.4.18; */

/* import "ds-thing/thing.sol"; */
/* import "ds-token/token.sol"; */
/* import "ds-value/value.sol"; */

/* import "./vox.sol"; */

contract SaiTubEvents {
    event LogNewCup(address indexed lad, bytes32 cup);
}

contract SaiTub is DSThing, SaiTubEvents {
    DSToken  public  sai;  // Stablecoin
    DSToken  public  sin;  // Debt (negative sai)

    DSToken  public  skr;  // Abstracted collateral
    ERC20    public  gem;  // Underlying collateral

    DSToken  public  gov;  // Governance token

    SaiVox   public  vox;  // Target price feed
    DSValue  public  pip;  // Reference price feed
    DSValue  public  pep;  // Governance price feed

    address  public  tap;  // Liquidator
    address  public  pit;  // Governance Vault

    uint256  public  axe;  // Liquidation penalty
    uint256  public  cap;  // Debt ceiling
    uint256  public  mat;  // Liquidation ratio
    uint256  public  tax;  // Stability fee
    uint256  public  fee;  // Governance fee
    uint256  public  gap;  // Join-Exit Spread

    bool     public  off;  // Cage flag
    bool     public  out;  // Post cage exit

    uint256  public  fit;  // REF per SKR (just before settlement)

    uint256  public  rho;  // Time of last drip
    uint256         _chi;  // Accumulated Tax Rates
    uint256         _rhi;  // Accumulated Tax + Fee Rates
    uint256  public  rum;  // Total normalised debt

    uint256                   public  cupi;
    mapping (bytes32 => Cup)  public  cups;

    struct Cup {
        address  lad;      // CDP owner
        uint256  ink;      // Locked collateral (in SKR)
        uint256  art;      // Outstanding normalised debt (tax only)
        uint256  ire;      // Outstanding normalised debt
    }

    function lad(bytes32 cup) public view returns (address) {
        return cups[cup].lad;
    }
    function ink(bytes32 cup) public view returns (uint) {
        return cups[cup].ink;
    }
    function tab(bytes32 cup) public returns (uint) {
        return rmul(cups[cup].art, chi());
    }
    function rap(bytes32 cup) public returns (uint) {
        return sub(rmul(cups[cup].ire, rhi()), tab(cup));
    }

    // Total CDP Debt
    function din() public returns (uint) {
        return rmul(rum, chi());
    }
    // Backing collateral
    function air() public view returns (uint) {
        return skr.balanceOf(this);
    }
    // Raw collateral
    function pie() public view returns (uint) {
        return gem.balanceOf(this);
    }

    //------------------------------------------------------------------

    function SaiTub(
        DSToken  sai_,
        DSToken  sin_,
        DSToken  skr_,
        ERC20    gem_,
        DSToken  gov_,
        DSValue  pip_,
        DSValue  pep_,
        SaiVox   vox_,
        address  pit_
    ) public {
        gem = gem_;
        skr = skr_;

        sai = sai_;
        sin = sin_;

        gov = gov_;
        pit = pit_;

        pip = pip_;
        pep = pep_;
        vox = vox_;

        axe = RAY;
        mat = RAY;
        tax = RAY;
        fee = RAY;
        gap = WAD;

        _chi = RAY;
        _rhi = RAY;

        rho = era();
    }

    function era() public constant returns (uint) {
        return block.timestamp;
    }

    //--Risk-parameter-config-------------------------------------------

    function mold(bytes32 param, uint val) public note auth {
        if      (param == 'cap') cap = val;
        else if (param == 'mat') { require(val >= RAY); mat = val; }
        else if (param == 'tax') { require(val >= RAY); drip(); tax = val; }
        else if (param == 'fee') { require(val >= RAY); drip(); fee = val; }
        else if (param == 'axe') { require(val >= RAY); axe = val; }
        else if (param == 'gap') { require(val >= WAD); gap = val; }
        else return;
    }

    //--Price-feed-setters----------------------------------------------

    function setPip(DSValue pip_) public note auth {
        pip = pip_;
    }
    function setPep(DSValue pep_) public note auth {
        pep = pep_;
    }
    function setVox(SaiVox vox_) public note auth {
        vox = vox_;
    }

    //--Tap-setter------------------------------------------------------
    function turn(address tap_) public note {
        require(tap  == 0);
        require(tap_ != 0);
        tap = tap_;
    }

    //--Collateral-wrapper----------------------------------------------

    // Wrapper ratio (gem per skr)
    function per() public view returns (uint ray) {
        return skr.totalSupply() == 0 ? RAY : rdiv(pie(), skr.totalSupply());
    }
    // Join price (gem per skr)
    function ask(uint wad) public view returns (uint) {
        return rmul(wad, wmul(per(), gap));
    }
    // Exit price (gem per skr)
    function bid(uint wad) public view returns (uint) {
        return rmul(wad, wmul(per(), sub(2 * WAD, gap)));
    }
    function join(uint wad) public note {
        require(!off);
        require(ask(wad) > 0);
        require(gem.transferFrom(msg.sender, this, ask(wad)));
        skr.mint(msg.sender, wad);
    }
    function exit(uint wad) public note {
        require(!off || out);
        require(gem.transfer(msg.sender, bid(wad)));
        skr.burn(msg.sender, wad);
    }

    //--Stability-fee-accumulation--------------------------------------

    // Accumulated Rates
    function chi() public returns (uint) {
        drip();
        return _chi;
    }
    function rhi() public returns (uint) {
        drip();
        return _rhi;
    }
    function drip() public note {
        if (off) return;

        var rho_ = era();
        var age = rho_ - rho;
        if (age == 0) return;    // optimised
        rho = rho_;

        var inc = RAY;

        if (tax != RAY) {  // optimised
            var _chi_ = _chi;
            inc = rpow(tax, age);
            _chi = rmul(_chi, inc);
            sai.mint(tap, rmul(sub(_chi, _chi_), rum));
        }

        // optimised
        if (fee != RAY) inc = rmul(inc, rpow(fee, age));
        if (inc != RAY) _rhi = rmul(_rhi, inc);
    }


    //--CDP-risk-indicator----------------------------------------------

    // Abstracted collateral price (ref per skr)
    function tag() public view returns (uint wad) {
        return off ? fit : wmul(per(), uint(pip.read()));
    }
    // Returns true if cup is well-collateralized
    function safe(bytes32 cup) public returns (bool) {
        var pro = rmul(tag(), ink(cup));
        var con = rmul(vox.par(), tab(cup));
        var min = rmul(con, mat);
        return pro >= min;
    }


    //--CDP-operations--------------------------------------------------

    function open() public note returns (bytes32 cup) {
        require(!off);
        cupi = add(cupi, 1);
        cup = bytes32(cupi);
        cups[cup].lad = msg.sender;
        LogNewCup(msg.sender, cup);
    }
    function give(bytes32 cup, address guy) public note {
        require(msg.sender == cups[cup].lad);
        require(guy != 0);
        cups[cup].lad = guy;
    }

    function lock(bytes32 cup, uint wad) public note {
        require(!off);
        cups[cup].ink = add(cups[cup].ink, wad);
        skr.pull(msg.sender, wad);
        require(cups[cup].ink == 0 || cups[cup].ink > 0.005 ether);
    }
    function free(bytes32 cup, uint wad) public note {
        require(msg.sender == cups[cup].lad);
        cups[cup].ink = sub(cups[cup].ink, wad);
        skr.push(msg.sender, wad);
        require(safe(cup));
        require(cups[cup].ink == 0 || cups[cup].ink > 0.005 ether);
    }

    function draw(bytes32 cup, uint wad) public note {
        require(!off);
        require(msg.sender == cups[cup].lad);
        require(rdiv(wad, chi()) > 0);

        cups[cup].art = add(cups[cup].art, rdiv(wad, chi()));
        rum = add(rum, rdiv(wad, chi()));

        cups[cup].ire = add(cups[cup].ire, rdiv(wad, rhi()));
        sai.mint(cups[cup].lad, wad);

        require(safe(cup));
        require(sai.totalSupply() <= cap);
    }
    function wipe(bytes32 cup, uint wad) public note {
        require(!off);

        var owe = rmul(wad, rdiv(rap(cup), tab(cup)));

        cups[cup].art = sub(cups[cup].art, rdiv(wad, chi()));
        rum = sub(rum, rdiv(wad, chi()));

        cups[cup].ire = sub(cups[cup].ire, rdiv(add(wad, owe), rhi()));
        sai.burn(msg.sender, wad);

        var (val, ok) = pep.peek();
        if (ok && val != 0) gov.move(msg.sender, pit, wdiv(owe, uint(val)));
    }

    function shut(bytes32 cup) public note {
        require(!off);
        require(msg.sender == cups[cup].lad);
        if (tab(cup) != 0) wipe(cup, tab(cup));
        if (ink(cup) != 0) free(cup, ink(cup));
        delete cups[cup];
    }

    function bite(bytes32 cup) public note {
        require(!safe(cup) || off);

        // Take on all of the debt, except unpaid fees
        var rue = tab(cup);
        sin.mint(tap, rue);
        rum = sub(rum, cups[cup].art);
        cups[cup].art = 0;
        cups[cup].ire = 0;

        // Amount owed in SKR, including liquidation penalty
        var owe = rdiv(rmul(rmul(rue, axe), vox.par()), tag());

        if (owe > cups[cup].ink) {
            owe = cups[cup].ink;
        }

        skr.push(tap, owe);
        cups[cup].ink = sub(cups[cup].ink, owe);
    }

    //------------------------------------------------------------------

    function cage(uint fit_, uint jam) public note auth {
        require(!off && fit_ != 0);
        off = true;
        axe = RAY;
        gap = WAD;
        fit = fit_;         // ref per skr
        require(gem.transfer(tap, jam));
    }
    function flow() public note auth {
        require(off);
        out = true;
    }
}

////// src/tap.sol
/// tap.sol -- liquidation engine (see also `vow`)

// Copyright (C) 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017  Rain Break <[email protected]>

// 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 ^0.4.18; */

/* import "./tub.sol"; */

contract SaiTap is DSThing {
    DSToken  public  sai;
    DSToken  public  sin;
    DSToken  public  skr;

    SaiVox   public  vox;
    SaiTub   public  tub;

    uint256  public  gap;  // Boom-Bust Spread
    bool     public  off;  // Cage flag
    uint256  public  fix;  // Cage price

    // Surplus
    function joy() public view returns (uint) {
        return sai.balanceOf(this);
    }
    // Bad debt
    function woe() public view returns (uint) {
        return sin.balanceOf(this);
    }
    // Collateral pending liquidation
    function fog() public view returns (uint) {
        return skr.balanceOf(this);
    }


    function SaiTap(SaiTub tub_) public {
        tub = tub_;

        sai = tub.sai();
        sin = tub.sin();
        skr = tub.skr();

        vox = tub.vox();

        gap = WAD;
    }

    function mold(bytes32 param, uint val) public note auth {
        if (param == 'gap') gap = val;
    }

    // Cancel debt
    function heal() public note {
        if (joy() == 0 || woe() == 0) return;  // optimised
        var wad = min(joy(), woe());
        sai.burn(wad);
        sin.burn(wad);
    }

    // Feed price (sai per skr)
    function s2s() public returns (uint) {
        var tag = tub.tag();    // ref per skr
        var par = vox.par();    // ref per sai
        return rdiv(tag, par);  // sai per skr
    }
    // Boom price (sai per skr)
    function bid(uint wad) public returns (uint) {
        return rmul(wad, wmul(s2s(), sub(2 * WAD, gap)));
    }
    // Bust price (sai per skr)
    function ask(uint wad) public returns (uint) {
        return rmul(wad, wmul(s2s(), gap));
    }
    function flip(uint wad) internal {
        require(ask(wad) > 0);
        skr.push(msg.sender, wad);
        sai.pull(msg.sender, ask(wad));
        heal();
    }
    function flop(uint wad) internal {
        skr.mint(sub(wad, fog()));
        flip(wad);
        require(joy() == 0);  // can't flop into surplus
    }
    function flap(uint wad) internal {
        heal();
        sai.push(msg.sender, bid(wad));
        skr.burn(msg.sender, wad);
    }
    function bust(uint wad) public note {
        require(!off);
        if (wad > fog()) flop(wad);
        else flip(wad);
    }
    function boom(uint wad) public note {
        require(!off);
        flap(wad);
    }

    //------------------------------------------------------------------

    function cage(uint fix_) public note auth {
        require(!off);
        off = true;
        fix = fix_;
    }
    function cash(uint wad) public note {
        require(off);
        sai.burn(msg.sender, wad);
        require(tub.gem().transfer(msg.sender, rmul(wad, fix)));
    }
    function mock(uint wad) public note {
        require(off);
        sai.mint(msg.sender, wad);
        require(tub.gem().transferFrom(msg.sender, this, rmul(wad, fix)));
    }
    function vent() public note {
        require(off);
        skr.burn(fog());
    }
}

////// src/top.sol
/// top.sol -- global settlement manager

// Copyright (C) 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017  Rain Break <[email protected]>

// 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 ^0.4.18; */

/* import "./tub.sol"; */
/* import "./tap.sol"; */

contract SaiTop is DSThing {
    SaiVox   public  vox;
    SaiTub   public  tub;
    SaiTap   public  tap;

    DSToken  public  sai;
    DSToken  public  sin;
    DSToken  public  skr;
    ERC20    public  gem;

    uint256  public  fix;  // sai cage price (gem per sai)
    uint256  public  fit;  // skr cage price (ref per skr)
    uint256  public  caged;
    uint256  public  cooldown = 6 hours;

    function SaiTop(SaiTub tub_, SaiTap tap_) public {
        tub = tub_;
        tap = tap_;

        vox = tub.vox();

        sai = tub.sai();
        sin = tub.sin();
        skr = tub.skr();
        gem = tub.gem();
    }

    function era() public view returns (uint) {
        return block.timestamp;
    }

    // force settlement of the system at a given price (sai per gem).
    // This is nearly the equivalent of biting all cups at once.
    // Important consideration: the gems associated with free skr can
    // be tapped to make sai whole.
    function cage(uint price) internal {
        require(!tub.off() && price != 0);
        caged = era();

        tub.drip();  // collect remaining fees
        tap.heal();  // absorb any pending fees

        fit = rmul(wmul(price, vox.par()), tub.per());
        // Most gems we can get per sai is the full balance of the tub.
        // If there is no sai issued, we should still be able to cage.
        if (sai.totalSupply() == 0) {
            fix = rdiv(WAD, price);
        } else {
            fix = min(rdiv(WAD, price), rdiv(tub.pie(), sai.totalSupply()));
        }

        tub.cage(fit, rmul(fix, sai.totalSupply()));
        tap.cage(fix);

        tap.vent();    // burn pending sale skr
    }
    // cage by reading the last value from the feed for the price
    function cage() public note auth {
        cage(rdiv(uint(tub.pip().read()), vox.par()));
    }

    function flow() public note {
        require(tub.off());
        var empty = tub.din() == 0 && tap.fog() == 0;
        var ended = era() > caged + cooldown;
        require(empty || ended);
        tub.flow();
    }

    function setCooldown(uint cooldown_) public auth {
        cooldown = cooldown_;
    }
}

////// src/mom.sol
/// mom.sol -- admin manager

// Copyright (C) 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017  Rain <[email protected]>

// 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 ^0.4.18; */

/* import 'ds-thing/thing.sol'; */
/* import './tub.sol'; */
/* import './top.sol'; */
/* import './tap.sol'; */

contract SaiMom is DSThing {
    SaiTub  public  tub;
    SaiTap  public  tap;
    SaiVox  public  vox;

    function SaiMom(SaiTub tub_, SaiTap tap_, SaiVox vox_) public {
        tub = tub_;
        tap = tap_;
        vox = vox_;
    }
    // Debt ceiling
    function setCap(uint wad) public note auth {
        tub.mold("cap", wad);
    }
    // Liquidation ratio
    function setMat(uint ray) public note auth {
        tub.mold("mat", ray);
        var axe = tub.axe();
        var mat = tub.mat();
        require(axe >= RAY && axe <= mat);
    }
    // Stability fee
    function setTax(uint ray) public note auth {
        tub.mold("tax", ray);
        var tax = tub.tax();
        require(RAY <= tax);
        require(tax < 1000001100000000000000000000);  // 10% / day
    }
    // Governance fee
    function setFee(uint ray) public note auth {
        tub.mold("fee", ray);
        var fee = tub.fee();
        require(RAY <= fee);
        require(fee < 1000001100000000000000000000);  // 10% / day
    }
    // Liquidation fee
    function setAxe(uint ray) public note auth {
        tub.mold("axe", ray);
        var axe = tub.axe();
        var mat = tub.mat();
        require(axe >= RAY && axe <= mat);
    }
    // Join/Exit Spread
    function setTubGap(uint wad) public note auth {
        tub.mold("gap", wad);
    }
    // ETH/USD Feed
    function setPip(DSValue pip_) public note auth {
        tub.setPip(pip_);
    }
    // MKR/USD Feed
    function setPep(DSValue pep_) public note auth {
        tub.setPep(pep_);
    }
    // TRFM
    function setVox(SaiVox vox_) public note auth {
        tub.setVox(vox_);
    }
    // Boom/Bust Spread
    function setTapGap(uint wad) public note auth {
        tap.mold("gap", wad);
        var gap = tap.gap();
        require(gap <= 1.05 ether);
        require(gap >= 0.95 ether);
    }
    // Rate of change of target price (per second)
    function setWay(uint ray) public note auth {
        require(ray < 1000001100000000000000000000);  // 10% / day
        require(ray >  999998800000000000000000000);
        vox.mold("way", ray);
    }
    function setHow(uint ray) public note auth {
        vox.tune(ray);
    }
}

// hevm: flattened sources of src/tub.sol
pragma solidity ^0.4.18;

////// lib/ds-guard/lib/ds-auth/src/auth.sol
// 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 ^0.4.13; */

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    function DSAuth() public {
        owner = msg.sender;
        LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        LogSetAuthority(authority);
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig));
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, this, sig);
        }
    }
}

////// lib/ds-spell/lib/ds-note/src/note.sol
/// note.sol -- the `note' modifier, for logging calls as events

// 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 ^0.4.13; */

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint              wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
        }

        LogNote(msg.sig, msg.sender, foo, bar, msg.value, msg.data);

        _;
    }
}

////// lib/ds-thing/lib/ds-math/src/math.sol
/// math.sol -- mixin for inline numerical wizardry

// 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 ^0.4.13; */

contract DSMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x);
    }

    function min(uint x, uint y) internal pure returns (uint z) {
        return x <= y ? x : y;
    }
    function max(uint x, uint y) internal pure returns (uint z) {
        return x >= y ? x : y;
    }
    function imin(int x, int y) internal pure returns (int z) {
        return x <= y ? x : y;
    }
    function imax(int x, int y) internal pure returns (int z) {
        return x >= y ? x : y;
    }

    uint constant WAD = 10 ** 18;
    uint constant RAY = 10 ** 27;

    function wmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), WAD / 2) / WAD;
    }
    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), RAY / 2) / RAY;
    }
    function wdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, WAD), y / 2) / y;
    }
    function rdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, RAY), y / 2) / y;
    }

    // This famous algorithm is called "exponentiation by squaring"
    // and calculates x^n with x as fixed-point and n as regular unsigned.
    //
    // It's O(log n), instead of O(n) for naive repeated multiplication.
    //
    // These facts are why it works:
    //
    //  If n is even, then x^n = (x^2)^(n/2).
    //  If n is odd,  then x^n = x * x^(n-1),
    //   and applying the equation for even x gives
    //    x^n = x * (x^2)^((n-1) / 2).
    //
    //  Also, EVM division is flooring and
    //    floor[(n-1) / 2] = floor[n / 2].
    //
    function rpow(uint x, uint n) internal pure returns (uint z) {
        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }
}

////// lib/ds-thing/src/thing.sol
// thing.sol - `auth` with handy mixins. your things should be DSThings

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import 'ds-auth/auth.sol'; */
/* import 'ds-note/note.sol'; */
/* import 'ds-math/math.sol'; */

contract DSThing is DSAuth, DSNote, DSMath {

    function S(string s) internal pure returns (bytes4) {
        return bytes4(keccak256(s));
    }

}

////// lib/ds-token/lib/ds-stop/src/stop.sol
/// stop.sol -- mixin for enable/disable functionality

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "ds-auth/auth.sol"; */
/* import "ds-note/note.sol"; */

contract DSStop is DSNote, DSAuth {

    bool public stopped;

    modifier stoppable {
        require(!stopped);
        _;
    }
    function stop() public auth note {
        stopped = true;
    }
    function start() public auth note {
        stopped = false;
    }

}

////// lib/ds-token/lib/erc20/src/erc20.sol
/// erc20.sol -- API for the ERC20 token standard

// See <https://github.com/ethereum/EIPs/issues/20>.

// This file likely does not meet the threshold of originality
// required for copyright to apply.  As a result, this is free and
// unencumbered software belonging to the public domain.

/* pragma solidity ^0.4.8; */

contract ERC20Events {
    event Approval(address indexed src, address indexed guy, uint wad);
    event Transfer(address indexed src, address indexed dst, uint wad);
}

contract ERC20 is ERC20Events {
    function totalSupply() public view returns (uint);
    function balanceOf(address guy) public view returns (uint);
    function allowance(address src, address guy) public view returns (uint);

    function approve(address guy, uint wad) public returns (bool);
    function transfer(address dst, uint wad) public returns (bool);
    function transferFrom(
        address src, address dst, uint wad
    ) public returns (bool);
}

////// lib/ds-token/src/base.sol
/// base.sol -- basic ERC20 implementation

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "erc20/erc20.sol"; */
/* import "ds-math/math.sol"; */

contract DSTokenBase is ERC20, DSMath {
    uint256                                            _supply;
    mapping (address => uint256)                       _balances;
    mapping (address => mapping (address => uint256))  _approvals;

    function DSTokenBase(uint supply) public {
        _balances[msg.sender] = supply;
        _supply = supply;
    }

    function totalSupply() public view returns (uint) {
        return _supply;
    }
    function balanceOf(address src) public view returns (uint) {
        return _balances[src];
    }
    function allowance(address src, address guy) public view returns (uint) {
        return _approvals[src][guy];
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        if (src != msg.sender) {
            _approvals[src][msg.sender] = sub(_approvals[src][msg.sender], wad);
        }

        _balances[src] = sub(_balances[src], wad);
        _balances[dst] = add(_balances[dst], wad);

        Transfer(src, dst, wad);

        return true;
    }

    function approve(address guy, uint wad) public returns (bool) {
        _approvals[msg.sender][guy] = wad;

        Approval(msg.sender, guy, wad);

        return true;
    }
}

////// lib/ds-token/src/token.sol
/// token.sol -- ERC20 implementation with minting and burning

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "ds-stop/stop.sol"; */

/* import "./base.sol"; */

contract DSToken is DSTokenBase(0), DSStop {

    bytes32  public  symbol;
    uint256  public  decimals = 18; // standard token precision. override to customize

    function DSToken(bytes32 symbol_) public {
        symbol = symbol_;
    }

    event Mint(address indexed guy, uint wad);
    event Burn(address indexed guy, uint wad);

    function approve(address guy) public stoppable returns (bool) {
        return super.approve(guy, uint(-1));
    }

    function approve(address guy, uint wad) public stoppable returns (bool) {
        return super.approve(guy, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        stoppable
        returns (bool)
    {
        if (src != msg.sender && _approvals[src][msg.sender] != uint(-1)) {
            _approvals[src][msg.sender] = sub(_approvals[src][msg.sender], wad);
        }

        _balances[src] = sub(_balances[src], wad);
        _balances[dst] = add(_balances[dst], wad);

        Transfer(src, dst, wad);

        return true;
    }

    function push(address dst, uint wad) public {
        transferFrom(msg.sender, dst, wad);
    }
    function pull(address src, uint wad) public {
        transferFrom(src, msg.sender, wad);
    }
    function move(address src, address dst, uint wad) public {
        transferFrom(src, dst, wad);
    }

    function mint(uint wad) public {
        mint(msg.sender, wad);
    }
    function burn(uint wad) public {
        burn(msg.sender, wad);
    }
    function mint(address guy, uint wad) public auth stoppable {
        _balances[guy] = add(_balances[guy], wad);
        _supply = add(_supply, wad);
        Mint(guy, wad);
    }
    function burn(address guy, uint wad) public auth stoppable {
        if (guy != msg.sender && _approvals[guy][msg.sender] != uint(-1)) {
            _approvals[guy][msg.sender] = sub(_approvals[guy][msg.sender], wad);
        }

        _balances[guy] = sub(_balances[guy], wad);
        _supply = sub(_supply, wad);
        Burn(guy, wad);
    }

    // Optional token name
    bytes32   public  name = "";

    function setName(bytes32 name_) public auth {
        name = name_;
    }
}

////// lib/ds-value/src/value.sol
/// value.sol - a value is a simple thing, it can be get and set

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import 'ds-thing/thing.sol'; */

contract DSValue is DSThing {
    bool    has;
    bytes32 val;
    function peek() public view returns (bytes32, bool) {
        return (val,has);
    }
    function read() public view returns (bytes32) {
        var (wut, haz) = peek();
        assert(haz);
        return wut;
    }
    function poke(bytes32 wut) public note auth {
        val = wut;
        has = true;
    }
    function void() public note auth {  // unset the value
        has = false;
    }
}

////// src/vox.sol
/// vox.sol -- target price feed

// Copyright (C) 2016, 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2016, 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017        Rain Break <[email protected]>

// 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 ^0.4.18; */

/* import "ds-thing/thing.sol"; */

contract SaiVox is DSThing {
    uint256  _par;
    uint256  _way;

    uint256  public  fix;
    uint256  public  how;
    uint256  public  tau;

    function SaiVox(uint par_) public {
        _par = fix = par_;
        _way = RAY;
        tau  = era();
    }

    function era() public view returns (uint) {
        return block.timestamp;
    }

    function mold(bytes32 param, uint val) public note auth {
        if (param == 'way') _way = val;
    }

    // Dai Target Price (ref per dai)
    function par() public returns (uint) {
        prod();
        return _par;
    }
    function way() public returns (uint) {
        prod();
        return _way;
    }

    function tell(uint256 ray) public note auth {
        fix = ray;
    }
    function tune(uint256 ray) public note auth {
        how = ray;
    }

    function prod() public note {
        var age = era() - tau;
        if (age == 0) return;  // optimised
        tau = era();

        if (_way != RAY) _par = rmul(_par, rpow(_way, age));  // optimised

        if (how == 0) return;  // optimised
        var wag = int128(how * age);
        _way = inj(prj(_way) + (fix < _par ? wag : -wag));
    }

    function inj(int128 x) internal pure returns (uint256) {
        return x >= 0 ? uint256(x) + RAY
            : rdiv(RAY, RAY + uint256(-x));
    }
    function prj(uint256 x) internal pure returns (int128) {
        return x >= RAY ? int128(x - RAY)
            : int128(RAY) - int128(rdiv(RAY, x));
    }
}

////// src/tub.sol
/// tub.sol -- simplified CDP engine (baby brother of `vat')

// Copyright (C) 2017  Nikolai Mushegian <[email protected]>
// Copyright (C) 2017  Daniel Brockman <[email protected]>
// Copyright (C) 2017  Rain Break <[email protected]>

// 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 ^0.4.18; */

/* import "ds-thing/thing.sol"; */
/* import "ds-token/token.sol"; */
/* import "ds-value/value.sol"; */

/* import "./vox.sol"; */

contract SaiTubEvents {
    event LogNewCup(address indexed lad, bytes32 cup);
}

contract SaiTub is DSThing, SaiTubEvents {
    DSToken  public  sai;  // Stablecoin
    DSToken  public  sin;  // Debt (negative sai)

    DSToken  public  skr;  // Abstracted collateral
    ERC20    public  gem;  // Underlying collateral

    DSToken  public  gov;  // Governance token

    SaiVox   public  vox;  // Target price feed
    DSValue  public  pip;  // Reference price feed
    DSValue  public  pep;  // Governance price feed

    address  public  tap;  // Liquidator
    address  public  pit;  // Governance Vault

    uint256  public  axe;  // Liquidation penalty
    uint256  public  cap;  // Debt ceiling
    uint256  public  mat;  // Liquidation ratio
    uint256  public  tax;  // Stability fee
    uint256  public  fee;  // Governance fee
    uint256  public  gap;  // Join-Exit Spread

    bool     public  off;  // Cage flag
    bool     public  out;  // Post cage exit

    uint256  public  fit;  // REF per SKR (just before settlement)

    uint256  public  rho;  // Time of last drip
    uint256         _chi;  // Accumulated Tax Rates
    uint256         _rhi;  // Accumulated Tax + Fee Rates
    uint256  public  rum;  // Total normalised debt

    uint256                   public  cupi;
    mapping (bytes32 => Cup)  public  cups;

    struct Cup {
        address  lad;      // CDP owner
        uint256  ink;      // Locked collateral (in SKR)
        uint256  art;      // Outstanding normalised debt (tax only)
        uint256  ire;      // Outstanding normalised debt
    }

    function lad(bytes32 cup) public view returns (address) {
        return cups[cup].lad;
    }
    function ink(bytes32 cup) public view returns (uint) {
        return cups[cup].ink;
    }
    function tab(bytes32 cup) public returns (uint) {
        return rmul(cups[cup].art, chi());
    }
    function rap(bytes32 cup) public returns (uint) {
        return sub(rmul(cups[cup].ire, rhi()), tab(cup));
    }

    // Total CDP Debt
    function din() public returns (uint) {
        return rmul(rum, chi());
    }
    // Backing collateral
    function air() public view returns (uint) {
        return skr.balanceOf(this);
    }
    // Raw collateral
    function pie() public view returns (uint) {
        return gem.balanceOf(this);
    }

    //------------------------------------------------------------------

    function SaiTub(
        DSToken  sai_,
        DSToken  sin_,
        DSToken  skr_,
        ERC20    gem_,
        DSToken  gov_,
        DSValue  pip_,
        DSValue  pep_,
        SaiVox   vox_,
        address  pit_
    ) public {
        gem = gem_;
        skr = skr_;

        sai = sai_;
        sin = sin_;

        gov = gov_;
        pit = pit_;

        pip = pip_;
        pep = pep_;
        vox = vox_;

        axe = RAY;
        mat = RAY;
        tax = RAY;
        fee = RAY;
        gap = WAD;

        _chi = RAY;
        _rhi = RAY;

        rho = era();
    }

    function era() public constant returns (uint) {
        return block.timestamp;
    }

    //--Risk-parameter-config-------------------------------------------

    function mold(bytes32 param, uint val) public note auth {
        if      (param == 'cap') cap = val;
        else if (param == 'mat') { require(val >= RAY); mat = val; }
        else if (param == 'tax') { require(val >= RAY); drip(); tax = val; }
        else if (param == 'fee') { require(val >= RAY); drip(); fee = val; }
        else if (param == 'axe') { require(val >= RAY); axe = val; }
        else if (param == 'gap') { require(val >= WAD); gap = val; }
        else return;
    }

    //--Price-feed-setters----------------------------------------------

    function setPip(DSValue pip_) public note auth {
        pip = pip_;
    }
    function setPep(DSValue pep_) public note auth {
        pep = pep_;
    }
    function setVox(SaiVox vox_) public note auth {
        vox = vox_;
    }

    //--Tap-setter------------------------------------------------------
    function turn(address tap_) public note {
        require(tap  == 0);
        require(tap_ != 0);
        tap = tap_;
    }

    //--Collateral-wrapper----------------------------------------------

    // Wrapper ratio (gem per skr)
    function per() public view returns (uint ray) {
        return skr.totalSupply() == 0 ? RAY : rdiv(pie(), skr.totalSupply());
    }
    // Join price (gem per skr)
    function ask(uint wad) public view returns (uint) {
        return rmul(wad, wmul(per(), gap));
    }
    // Exit price (gem per skr)
    function bid(uint wad) public view returns (uint) {
        return rmul(wad, wmul(per(), sub(2 * WAD, gap)));
    }
    function join(uint wad) public note {
        require(!off);
        require(ask(wad) > 0);
        require(gem.transferFrom(msg.sender, this, ask(wad)));
        skr.mint(msg.sender, wad);
    }
    function exit(uint wad) public note {
        require(!off || out);
        require(gem.transfer(msg.sender, bid(wad)));
        skr.burn(msg.sender, wad);
    }

    //--Stability-fee-accumulation--------------------------------------

    // Accumulated Rates
    function chi() public returns (uint) {
        drip();
        return _chi;
    }
    function rhi() public returns (uint) {
        drip();
        return _rhi;
    }
    function drip() public note {
        if (off) return;

        var rho_ = era();
        var age = rho_ - rho;
        if (age == 0) return;    // optimised
        rho = rho_;

        var inc = RAY;

        if (tax != RAY) {  // optimised
            var _chi_ = _chi;
            inc = rpow(tax, age);
            _chi = rmul(_chi, inc);
            sai.mint(tap, rmul(sub(_chi, _chi_), rum));
        }

        // optimised
        if (fee != RAY) inc = rmul(inc, rpow(fee, age));
        if (inc != RAY) _rhi = rmul(_rhi, inc);
    }


    //--CDP-risk-indicator----------------------------------------------

    // Abstracted collateral price (ref per skr)
    function tag() public view returns (uint wad) {
        return off ? fit : wmul(per(), uint(pip.read()));
    }
    // Returns true if cup is well-collateralized
    function safe(bytes32 cup) public returns (bool) {
        var pro = rmul(tag(), ink(cup));
        var con = rmul(vox.par(), tab(cup));
        var min = rmul(con, mat);
        return pro >= min;
    }


    //--CDP-operations--------------------------------------------------

    function open() public note returns (bytes32 cup) {
        require(!off);
        cupi = add(cupi, 1);
        cup = bytes32(cupi);
        cups[cup].lad = msg.sender;
        LogNewCup(msg.sender, cup);
    }
    function give(bytes32 cup, address guy) public note {
        require(msg.sender == cups[cup].lad);
        require(guy != 0);
        cups[cup].lad = guy;
    }

    function lock(bytes32 cup, uint wad) public note {
        require(!off);
        cups[cup].ink = add(cups[cup].ink, wad);
        skr.pull(msg.sender, wad);
        require(cups[cup].ink == 0 || cups[cup].ink > 0.005 ether);
    }
    function free(bytes32 cup, uint wad) public note {
        require(msg.sender == cups[cup].lad);
        cups[cup].ink = sub(cups[cup].ink, wad);
        skr.push(msg.sender, wad);
        require(safe(cup));
        require(cups[cup].ink == 0 || cups[cup].ink > 0.005 ether);
    }

    function draw(bytes32 cup, uint wad) public note {
        require(!off);
        require(msg.sender == cups[cup].lad);
        require(rdiv(wad, chi()) > 0);

        cups[cup].art = add(cups[cup].art, rdiv(wad, chi()));
        rum = add(rum, rdiv(wad, chi()));

        cups[cup].ire = add(cups[cup].ire, rdiv(wad, rhi()));
        sai.mint(cups[cup].lad, wad);

        require(safe(cup));
        require(sai.totalSupply() <= cap);
    }
    function wipe(bytes32 cup, uint wad) public note {
        require(!off);

        var owe = rmul(wad, rdiv(rap(cup), tab(cup)));

        cups[cup].art = sub(cups[cup].art, rdiv(wad, chi()));
        rum = sub(rum, rdiv(wad, chi()));

        cups[cup].ire = sub(cups[cup].ire, rdiv(add(wad, owe), rhi()));
        sai.burn(msg.sender, wad);

        var (val, ok) = pep.peek();
        if (ok && val != 0) gov.move(msg.sender, pit, wdiv(owe, uint(val)));
    }

    function shut(bytes32 cup) public note {
        require(!off);
        require(msg.sender == cups[cup].lad);
        if (tab(cup) != 0) wipe(cup, tab(cup));
        if (ink(cup) != 0) free(cup, ink(cup));
        delete cups[cup];
    }

    function bite(bytes32 cup) public note {
        require(!safe(cup) || off);

        // Take on all of the debt, except unpaid fees
        var rue = tab(cup);
        sin.mint(tap, rue);
        rum = sub(rum, cups[cup].art);
        cups[cup].art = 0;
        cups[cup].ire = 0;

        // Amount owed in SKR, including liquidation penalty
        var owe = rdiv(rmul(rmul(rue, axe), vox.par()), tag());

        if (owe > cups[cup].ink) {
            owe = cups[cup].ink;
        }

        skr.push(tap, owe);
        cups[cup].ink = sub(cups[cup].ink, owe);
    }

    //------------------------------------------------------------------

    function cage(uint fit_, uint jam) public note auth {
        require(!off && fit_ != 0);
        off = true;
        axe = RAY;
        gap = WAD;
        fit = fit_;         // ref per skr
        require(gem.transfer(tap, jam));
    }
    function flow() public note auth {
        require(off);
        out = true;
    }
}

// hevm: flattened sources of src/chief.sol
pragma solidity >=0.4.23;

////// lib/ds-roles/lib/ds-auth/src/auth.sol
// 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 >=0.4.23; */

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    constructor() public {
        owner = msg.sender;
        emit LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        emit LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig), "ds-auth-unauthorized");
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, address(this), sig);
        }
    }
}

////// lib/ds-roles/src/roles.sol
// roles.sol - roled based authentication

// Copyright (C) 2017  DappHub, LLC

// 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 >=0.4.23; */

/* import 'ds-auth/auth.sol'; */

contract DSRoles is DSAuth, DSAuthority
{
    mapping(address=>bool) _root_users;
    mapping(address=>bytes32) _user_roles;
    mapping(address=>mapping(bytes4=>bytes32)) _capability_roles;
    mapping(address=>mapping(bytes4=>bool)) _public_capabilities;

    function getUserRoles(address who)
        public
        view
        returns (bytes32)
    {
        return _user_roles[who];
    }

    function getCapabilityRoles(address code, bytes4 sig)
        public
        view
        returns (bytes32)
    {
        return _capability_roles[code][sig];
    }

    function isUserRoot(address who)
        public
        view
        returns (bool)
    {
        return _root_users[who];
    }

    function isCapabilityPublic(address code, bytes4 sig)
        public
        view
        returns (bool)
    {
        return _public_capabilities[code][sig];
    }

    function hasUserRole(address who, uint8 role)
        public
        view
        returns (bool)
    {
        bytes32 roles = getUserRoles(who);
        bytes32 shifted = bytes32(uint256(uint256(2) ** uint256(role)));
        return bytes32(0) != roles & shifted;
    }

    function canCall(address caller, address code, bytes4 sig)
        public
        view
        returns (bool)
    {
        if( isUserRoot(caller) || isCapabilityPublic(code, sig) ) {
            return true;
        } else {
            bytes32 has_roles = getUserRoles(caller);
            bytes32 needs_one_of = getCapabilityRoles(code, sig);
            return bytes32(0) != has_roles & needs_one_of;
        }
    }

    function BITNOT(bytes32 input) internal pure returns (bytes32 output) {
        return (input ^ bytes32(uint(-1)));
    }

    function setRootUser(address who, bool enabled)
        public
        auth
    {
        _root_users[who] = enabled;
    }

    function setUserRole(address who, uint8 role, bool enabled)
        public
        auth
    {
        bytes32 last_roles = _user_roles[who];
        bytes32 shifted = bytes32(uint256(uint256(2) ** uint256(role)));
        if( enabled ) {
            _user_roles[who] = last_roles | shifted;
        } else {
            _user_roles[who] = last_roles & BITNOT(shifted);
        }
    }

    function setPublicCapability(address code, bytes4 sig, bool enabled)
        public
        auth
    {
        _public_capabilities[code][sig] = enabled;
    }

    function setRoleCapability(uint8 role, address code, bytes4 sig, bool enabled)
        public
        auth
    {
        bytes32 last_roles = _capability_roles[code][sig];
        bytes32 shifted = bytes32(uint256(uint256(2) ** uint256(role)));
        if( enabled ) {
            _capability_roles[code][sig] = last_roles | shifted;
        } else {
            _capability_roles[code][sig] = last_roles & BITNOT(shifted);
        }

    }

}

////// lib/ds-thing/lib/ds-math/src/math.sol
/// math.sol -- mixin for inline numerical wizardry

// 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 >0.4.13; */

contract DSMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, "ds-math-add-overflow");
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, "ds-math-sub-underflow");
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, "ds-math-mul-overflow");
    }

    function min(uint x, uint y) internal pure returns (uint z) {
        return x <= y ? x : y;
    }
    function max(uint x, uint y) internal pure returns (uint z) {
        return x >= y ? x : y;
    }
    function imin(int x, int y) internal pure returns (int z) {
        return x <= y ? x : y;
    }
    function imax(int x, int y) internal pure returns (int z) {
        return x >= y ? x : y;
    }

    uint constant WAD = 10 ** 18;
    uint constant RAY = 10 ** 27;

    function wmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), WAD / 2) / WAD;
    }
    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), RAY / 2) / RAY;
    }
    function wdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, WAD), y / 2) / y;
    }
    function rdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, RAY), y / 2) / y;
    }

    // This famous algorithm is called "exponentiation by squaring"
    // and calculates x^n with x as fixed-point and n as regular unsigned.
    //
    // It's O(log n), instead of O(n) for naive repeated multiplication.
    //
    // These facts are why it works:
    //
    //  If n is even, then x^n = (x^2)^(n/2).
    //  If n is odd,  then x^n = x * x^(n-1),
    //   and applying the equation for even x gives
    //    x^n = x * (x^2)^((n-1) / 2).
    //
    //  Also, EVM division is flooring and
    //    floor[(n-1) / 2] = floor[n / 2].
    //
    function rpow(uint x, uint n) internal pure returns (uint z) {
        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }
}

////// lib/ds-thing/lib/ds-note/src/note.sol
/// note.sol -- the `note' modifier, for logging calls as events

// 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 >=0.4.23; */

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint256           wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;
        uint256 wad;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
            wad := callvalue
        }

        emit LogNote(msg.sig, msg.sender, foo, bar, wad, msg.data);

        _;
    }
}

////// lib/ds-thing/src/thing.sol
// thing.sol - `auth` with handy mixins. your things should be DSThings

// Copyright (C) 2017  DappHub, LLC

// 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 >=0.4.23; */

/* import 'ds-auth/auth.sol'; */
/* import 'ds-note/note.sol'; */
/* import 'ds-math/math.sol'; */

contract DSThing is DSAuth, DSNote, DSMath {
    function S(string memory s) internal pure returns (bytes4) {
        return bytes4(keccak256(abi.encodePacked(s)));
    }

}

////// lib/ds-token/lib/ds-stop/src/stop.sol
/// stop.sol -- mixin for enable/disable functionality

// Copyright (C) 2017  DappHub, LLC

// 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 >=0.4.23; */

/* import "ds-auth/auth.sol"; */
/* import "ds-note/note.sol"; */

contract DSStop is DSNote, DSAuth {
    bool public stopped;

    modifier stoppable {
        require(!stopped, "ds-stop-is-stopped");
        _;
    }
    function stop() public auth note {
        stopped = true;
    }
    function start() public auth note {
        stopped = false;
    }

}

////// lib/ds-token/lib/erc20/src/erc20.sol
/// erc20.sol -- API for the ERC20 token standard

// See <https://github.com/ethereum/EIPs/issues/20>.

// This file likely does not meet the threshold of originality
// required for copyright to apply.  As a result, this is free and
// unencumbered software belonging to the public domain.

/* pragma solidity >0.4.20; */

contract ERC20Events {
    event Approval(address indexed src, address indexed guy, uint wad);
    event Transfer(address indexed src, address indexed dst, uint wad);
}

contract ERC20 is ERC20Events {
    function totalSupply() public view returns (uint);
    function balanceOf(address guy) public view returns (uint);
    function allowance(address src, address guy) public view returns (uint);

    function approve(address guy, uint wad) public returns (bool);
    function transfer(address dst, uint wad) public returns (bool);
    function transferFrom(
        address src, address dst, uint wad
    ) public returns (bool);
}

////// lib/ds-token/src/base.sol
/// base.sol -- basic ERC20 implementation

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// 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 >=0.4.23; */

/* import "erc20/erc20.sol"; */
/* import "ds-math/math.sol"; */

contract DSTokenBase is ERC20, DSMath {
    uint256                                            _supply;
    mapping (address => uint256)                       _balances;
    mapping (address => mapping (address => uint256))  _approvals;

    constructor(uint supply) public {
        _balances[msg.sender] = supply;
        _supply = supply;
    }

    function totalSupply() public view returns (uint) {
        return _supply;
    }
    function balanceOf(address src) public view returns (uint) {
        return _balances[src];
    }
    function allowance(address src, address guy) public view returns (uint) {
        return _approvals[src][guy];
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        if (src != msg.sender) {
            require(_approvals[src][msg.sender] >= wad, "ds-token-insufficient-approval");
            _approvals[src][msg.sender] = sub(_approvals[src][msg.sender], wad);
        }

        require(_balances[src] >= wad, "ds-token-insufficient-balance");
        _balances[src] = sub(_balances[src], wad);
        _balances[dst] = add(_balances[dst], wad);

        emit Transfer(src, dst, wad);

        return true;
    }

    function approve(address guy, uint wad) public returns (bool) {
        _approvals[msg.sender][guy] = wad;

        emit Approval(msg.sender, guy, wad);

        return true;
    }
}

////// lib/ds-token/src/token.sol
/// token.sol -- ERC20 implementation with minting and burning

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// 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 >=0.4.23; */

/* import "ds-stop/stop.sol"; */

/* import "./base.sol"; */

contract DSToken is DSTokenBase(0), DSStop {

    bytes32  public  symbol;
    uint256  public  decimals = 18; // standard token precision. override to customize

    constructor(bytes32 symbol_) public {
        symbol = symbol_;
    }

    event Mint(address indexed guy, uint wad);
    event Burn(address indexed guy, uint wad);

    function approve(address guy) public stoppable returns (bool) {
        return super.approve(guy, uint(-1));
    }

    function approve(address guy, uint wad) public stoppable returns (bool) {
        return super.approve(guy, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        stoppable
        returns (bool)
    {
        if (src != msg.sender && _approvals[src][msg.sender] != uint(-1)) {
            require(_approvals[src][msg.sender] >= wad, "ds-token-insufficient-approval");
            _approvals[src][msg.sender] = sub(_approvals[src][msg.sender], wad);
        }

        require(_balances[src] >= wad, "ds-token-insufficient-balance");
        _balances[src] = sub(_balances[src], wad);
        _balances[dst] = add(_balances[dst], wad);

        emit Transfer(src, dst, wad);

        return true;
    }

    function push(address dst, uint wad) public {
        transferFrom(msg.sender, dst, wad);
    }
    function pull(address src, uint wad) public {
        transferFrom(src, msg.sender, wad);
    }
    function move(address src, address dst, uint wad) public {
        transferFrom(src, dst, wad);
    }

    function mint(uint wad) public {
        mint(msg.sender, wad);
    }
    function burn(uint wad) public {
        burn(msg.sender, wad);
    }
    function mint(address guy, uint wad) public auth stoppable {
        _balances[guy] = add(_balances[guy], wad);
        _supply = add(_supply, wad);
        emit Mint(guy, wad);
    }
    function burn(address guy, uint wad) public auth stoppable {
        if (guy != msg.sender && _approvals[guy][msg.sender] != uint(-1)) {
            require(_approvals[guy][msg.sender] >= wad, "ds-token-insufficient-approval");
            _approvals[guy][msg.sender] = sub(_approvals[guy][msg.sender], wad);
        }

        require(_balances[guy] >= wad, "ds-token-insufficient-balance");
        _balances[guy] = sub(_balances[guy], wad);
        _supply = sub(_supply, wad);
        emit Burn(guy, wad);
    }

    // Optional token name
    bytes32   public  name = "";

    function setName(bytes32 name_) public auth {
        name = name_;
    }
}

////// src/chief.sol
// chief.sol - select an authority by consensus

// Copyright (C) 2017  DappHub, LLC

// 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 >=0.4.23; */

/* import 'ds-token/token.sol'; */
/* import 'ds-roles/roles.sol'; */
/* import 'ds-thing/thing.sol'; */

// The right way to use this contract is probably to mix it with some kind
// of `DSAuthority`, like with `ds-roles`.
//   SEE DSChief
contract DSChiefApprovals is DSThing {
    mapping(bytes32=>address[]) public slates;
    mapping(address=>bytes32) public votes;
    mapping(address=>uint256) public approvals;
    mapping(address=>uint256) public deposits;
    DSToken public GOV; // voting token that gets locked up
    DSToken public IOU; // non-voting representation of a token, for e.g. secondary voting mechanisms
    address public hat; // the chieftain's hat

    uint256 public MAX_YAYS;

    event Etch(bytes32 indexed slate);

    // IOU constructed outside this contract reduces deployment costs significantly
    // lock/free/vote are quite sensitive to token invariants. Caution is advised.
    constructor(DSToken GOV_, DSToken IOU_, uint MAX_YAYS_) public
    {
        GOV = GOV_;
        IOU = IOU_;
        MAX_YAYS = MAX_YAYS_;
    }

    function lock(uint wad)
        public
        note
    {
        GOV.pull(msg.sender, wad);
        IOU.mint(msg.sender, wad);
        deposits[msg.sender] = add(deposits[msg.sender], wad);
        addWeight(wad, votes[msg.sender]);
    }

    function free(uint wad)
        public
        note
    {
        deposits[msg.sender] = sub(deposits[msg.sender], wad);
        subWeight(wad, votes[msg.sender]);
        IOU.burn(msg.sender, wad);
        GOV.push(msg.sender, wad);
    }

    function etch(address[] memory yays)
        public
        note
        returns (bytes32 slate)
    {
        require( yays.length <= MAX_YAYS );
        requireByteOrderedSet(yays);

        bytes32 hash = keccak256(abi.encodePacked(yays));
        slates[hash] = yays;
        emit Etch(hash);
        return hash;
    }

    function vote(address[] memory yays) public returns (bytes32)
        // note  both sub-calls note
    {
        bytes32 slate = etch(yays);
        vote(slate);
        return slate;
    }

    function vote(bytes32 slate)
        public
        note
    {
        require(slates[slate].length > 0 || 
            slate == 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470, "ds-chief-invalid-slate");
        uint weight = deposits[msg.sender];
        subWeight(weight, votes[msg.sender]);
        votes[msg.sender] = slate;
        addWeight(weight, votes[msg.sender]);
    }

    // like `drop`/`swap` except simply "elect this address if it is higher than current hat"
    function lift(address whom)
        public
        note
    {
        require(approvals[whom] > approvals[hat]);
        hat = whom;
    }

    function addWeight(uint weight, bytes32 slate)
        internal
    {
        address[] storage yays = slates[slate];
        for( uint i = 0; i < yays.length; i++) {
            approvals[yays[i]] = add(approvals[yays[i]], weight);
        }
    }

    function subWeight(uint weight, bytes32 slate)
        internal
    {
        address[] storage yays = slates[slate];
        for( uint i = 0; i < yays.length; i++) {
            approvals[yays[i]] = sub(approvals[yays[i]], weight);
        }
    }

    // Throws unless the array of addresses is a ordered set.
    function requireByteOrderedSet(address[] memory yays)
        internal
        pure
    {
        if( yays.length == 0 || yays.length == 1 ) {
            return;
        }
        for( uint i = 0; i < yays.length - 1; i++ ) {
            // strict inequality ensures both ordering and uniqueness
            require(uint(yays[i]) < uint(yays[i+1]));
        }
    }
}


// `hat` address is unique root user (has every role) and the
// unique owner of role 0 (typically 'sys' or 'internal')
contract DSChief is DSRoles, DSChiefApprovals {

    constructor(DSToken GOV, DSToken IOU, uint MAX_YAYS)
             DSChiefApprovals (GOV, IOU, MAX_YAYS)
        public
    {
        authority = this;
        owner = address(0);
    }

    function setOwner(address owner_) public {
        owner_;
        revert();
    }

    function setAuthority(DSAuthority authority_) public {
        authority_;
        revert();
    }

    function isUserRoot(address who)
        public view
        returns (bool)
    {
        return (who == hat);
    }
    function setRootUser(address who, bool enabled) public {
        who; enabled;
        revert();
    }
}

// hevm: flattened sources of /nix/store/b2bvh9ljr3yljrdz6lm764hdyj7nk4iy-ds-pause-f43edc1/src/pause.sol
pragma solidity >=0.4.23 >=0.5.0 <0.6.0;

////// /nix/store/6qq1ps6wrikrl6ha3q33739dbs2wg2hb-ds-note/dapp/ds-note/src/note.sol
/// note.sol -- the `note' modifier, for logging calls as events

// 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 >=0.4.23; */

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint256           wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;
        uint256 wad;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
            wad := callvalue
        }

        emit LogNote(msg.sig, msg.sender, foo, bar, wad, msg.data);

        _;
    }
}

////// /nix/store/r1w3fgb8wh0c2qn0i8jg95sv99l5nh7j-ds-auth/dapp/ds-auth/src/auth.sol
// 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 >=0.4.23; */

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    constructor() public {
        owner = msg.sender;
        emit LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        emit LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig), "ds-auth-unauthorized");
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, address(this), sig);
        }
    }
}

////// /nix/store/b2bvh9ljr3yljrdz6lm764hdyj7nk4iy-ds-pause-f43edc1/src/pause.sol
// Copyright (C) 2019 David Terry <[email protected]>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

/* pragma solidity >=0.5.0 <0.6.0; */

/* import {DSNote} from "ds-note/note.sol"; */
/* import {DSAuth, DSAuthority} from "ds-auth/auth.sol"; */

contract DSPause is DSAuth, DSNote {

    // --- admin ---

    modifier wait { require(msg.sender == address(proxy), "ds-pause-undelayed-call"); _; }

    function setOwner(address owner_) public wait {
        owner = owner_;
        emit LogSetOwner(owner);
    }
    function setAuthority(DSAuthority authority_) public wait {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }
    function setDelay(uint delay_) public note wait {
        delay = delay_;
    }

    // --- math ---

    function add(uint x, uint y) internal pure returns (uint z) {
        z = x + y;
        require(z >= x, "ds-pause-addition-overflow");
    }

    // --- data ---

    mapping (bytes32 => bool) public plans;
    DSPauseProxy public proxy;
    uint         public delay;

    // --- init ---

    constructor(uint delay_, address owner_, DSAuthority authority_) public {
        delay = delay_;
        owner = owner_;
        authority = authority_;
        proxy = new DSPauseProxy();
    }

    // --- util ---

    function hash(address usr, bytes32 tag, bytes memory fax, uint eta)
        internal pure
        returns (bytes32)
    {
        return keccak256(abi.encode(usr, tag, fax, eta));
    }

    function soul(address usr)
        internal view
        returns (bytes32 tag)
    {
        assembly { tag := extcodehash(usr) }
    }

    // --- operations ---

    function plot(address usr, bytes32 tag, bytes memory fax, uint eta)
        public note auth
    {
        require(eta >= add(now, delay), "ds-pause-delay-not-respected");
        plans[hash(usr, tag, fax, eta)] = true;
    }

    function drop(address usr, bytes32 tag, bytes memory fax, uint eta)
        public note auth
    {
        plans[hash(usr, tag, fax, eta)] = false;
    }

    function exec(address usr, bytes32 tag, bytes memory fax, uint eta)
        public note
        returns (bytes memory out)
    {
        require(plans[hash(usr, tag, fax, eta)], "ds-pause-unplotted-plan");
        require(soul(usr) == tag,                "ds-pause-wrong-codehash");
        require(now >= eta,                      "ds-pause-premature-exec");

        plans[hash(usr, tag, fax, eta)] = false;

        out = proxy.exec(usr, fax);
        require(proxy.owner() == address(this), "ds-pause-illegal-storage-change");
    }
}

// plans are executed in an isolated storage context to protect the pause from
// malicious storage modification during plan execution
contract DSPauseProxy {
    address public owner;
    modifier auth { require(msg.sender == owner, "ds-pause-proxy-unauthorized"); _; }
    constructor() public { owner = msg.sender; }

    function exec(address usr, bytes memory fax)
        public auth
        returns (bytes memory out)
    {
        bool ok;
        (ok, out) = usr.delegatecall(fax);
        require(ok, "ds-pause-delegatecall-error");
    }
}

// hevm: flattened sources of src/guard.sol
pragma solidity ^0.4.13;

////// lib/ds-auth/src/auth.sol
// 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 ^0.4.13; */

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    function DSAuth() public {
        owner = msg.sender;
        LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        LogSetAuthority(authority);
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig));
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, this, sig);
        }
    }
}

////// src/guard.sol
// guard.sol -- simple whitelist implementation of DSAuthority

// Copyright (C) 2017  DappHub, LLC

// 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 ^0.4.13; */

/* import "ds-auth/auth.sol"; */

contract DSGuardEvents {
    event LogPermit(
        bytes32 indexed src,
        bytes32 indexed dst,
        bytes32 indexed sig
    );

    event LogForbid(
        bytes32 indexed src,
        bytes32 indexed dst,
        bytes32 indexed sig
    );
}

contract DSGuard is DSAuth, DSAuthority, DSGuardEvents {
    bytes32 constant public ANY = bytes32(uint(-1));

    mapping (bytes32 => mapping (bytes32 => mapping (bytes32 => bool))) acl;

    function canCall(
        address src_, address dst_, bytes4 sig
    ) public view returns (bool) {
        var src = bytes32(src_);
        var dst = bytes32(dst_);

        return acl[src][dst][sig]
            || acl[src][dst][ANY]
            || acl[src][ANY][sig]
            || acl[src][ANY][ANY]
            || acl[ANY][dst][sig]
            || acl[ANY][dst][ANY]
            || acl[ANY][ANY][sig]
            || acl[ANY][ANY][ANY];
    }

    function permit(bytes32 src, bytes32 dst, bytes32 sig) public auth {
        acl[src][dst][sig] = true;
        LogPermit(src, dst, sig);
    }

    function forbid(bytes32 src, bytes32 dst, bytes32 sig) public auth {
        acl[src][dst][sig] = false;
        LogForbid(src, dst, sig);
    }

    function permit(address src, address dst, bytes32 sig) public {
        permit(bytes32(src), bytes32(dst), sig);
    }
    function forbid(address src, address dst, bytes32 sig) public {
        forbid(bytes32(src), bytes32(dst), sig);
    }

}

contract DSGuardFactory {
    mapping (address => bool)  public  isGuard;

    function newGuard() public returns (DSGuard guard) {
        guard = new DSGuard();
        guard.setOwner(msg.sender);
        isGuard[guard] = true;
    }
}