diff options
Diffstat (limited to 'test/compilationTests/zeppelin/token/VestedToken.sol')
-rw-r--r-- | test/compilationTests/zeppelin/token/VestedToken.sol | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/test/compilationTests/zeppelin/token/VestedToken.sol b/test/compilationTests/zeppelin/token/VestedToken.sol new file mode 100644 index 00000000..b7748b09 --- /dev/null +++ b/test/compilationTests/zeppelin/token/VestedToken.sol @@ -0,0 +1,248 @@ +pragma solidity ^0.4.11; + +import "../math/Math.sol"; +import "./StandardToken.sol"; +import "./LimitedTransferToken.sol"; + +/** + * @title Vested token + * @dev Tokens that can be vested for a group of addresses. + */ +contract VestedToken is StandardToken, LimitedTransferToken { + + uint256 MAX_GRANTS_PER_ADDRESS = 20; + + struct TokenGrant { + address granter; // 20 bytes + uint256 value; // 32 bytes + uint64 cliff; + uint64 vesting; + uint64 start; // 3 * 8 = 24 bytes + bool revokable; + bool burnsOnRevoke; // 2 * 1 = 2 bits? or 2 bytes? + } // total 78 bytes = 3 sstore per operation (32 per sstore) + + mapping (address => TokenGrant[]) public grants; + + event NewTokenGrant(address indexed from, address indexed to, uint256 value, uint256 grantId); + + /** + * @dev Grant tokens to a specified address + * @param _to address The address which the tokens will be granted to. + * @param _value uint256 The amount of tokens to be granted. + * @param _start uint64 Time of the beginning of the grant. + * @param _cliff uint64 Time of the cliff period. + * @param _vesting uint64 The vesting period. + */ + function grantVestedTokens( + address _to, + uint256 _value, + uint64 _start, + uint64 _cliff, + uint64 _vesting, + bool _revokable, + bool _burnsOnRevoke + ) public { + + // Check for date inconsistencies that may cause unexpected behavior + if (_cliff < _start || _vesting < _cliff) { + throw; + } + + if (tokenGrantsCount(_to) > MAX_GRANTS_PER_ADDRESS) throw; // To prevent a user being spammed and have his balance locked (out of gas attack when calculating vesting). + + uint256 count = grants[_to].push( + TokenGrant( + _revokable ? msg.sender : 0, // avoid storing an extra 20 bytes when it is non-revokable + _value, + _cliff, + _vesting, + _start, + _revokable, + _burnsOnRevoke + ) + ); + + transfer(_to, _value); + + NewTokenGrant(msg.sender, _to, _value, count - 1); + } + + /** + * @dev Revoke the grant of tokens of a specifed address. + * @param _holder The address which will have its tokens revoked. + * @param _grantId The id of the token grant. + */ + function revokeTokenGrant(address _holder, uint256 _grantId) public { + TokenGrant grant = grants[_holder][_grantId]; + + if (!grant.revokable) { // Check if grant was revokable + throw; + } + + if (grant.granter != msg.sender) { // Only granter can revoke it + throw; + } + + address receiver = grant.burnsOnRevoke ? 0xdead : msg.sender; + + uint256 nonVested = nonVestedTokens(grant, uint64(now)); + + // remove grant from array + delete grants[_holder][_grantId]; + grants[_holder][_grantId] = grants[_holder][grants[_holder].length.sub(1)]; + grants[_holder].length -= 1; + + balances[receiver] = balances[receiver].add(nonVested); + balances[_holder] = balances[_holder].sub(nonVested); + + Transfer(_holder, receiver, nonVested); + } + + + /** + * @dev Calculate the total amount of transferable tokens of a holder at a given time + * @param holder address The address of the holder + * @param time uint64 The specific time. + * @return An uint256 representing a holder's total amount of transferable tokens. + */ + function transferableTokens(address holder, uint64 time) constant public returns (uint256) { + uint256 grantIndex = tokenGrantsCount(holder); + + if (grantIndex == 0) return balanceOf(holder); // shortcut for holder without grants + + // Iterate through all the grants the holder has, and add all non-vested tokens + uint256 nonVested = 0; + for (uint256 i = 0; i < grantIndex; i++) { + nonVested = SafeMath.add(nonVested, nonVestedTokens(grants[holder][i], time)); + } + + // Balance - totalNonVested is the amount of tokens a holder can transfer at any given time + uint256 vestedTransferable = SafeMath.sub(balanceOf(holder), nonVested); + + // Return the minimum of how many vested can transfer and other value + // in case there are other limiting transferability factors (default is balanceOf) + return Math.min256(vestedTransferable, super.transferableTokens(holder, time)); + } + + /** + * @dev Check the amount of grants that an address has. + * @param _holder The holder of the grants. + * @return A uint256 representing the total amount of grants. + */ + function tokenGrantsCount(address _holder) constant returns (uint256 index) { + return grants[_holder].length; + } + + /** + * @dev Calculate amount of vested tokens at a specifc time. + * @param tokens uint256 The amount of tokens grantted. + * @param time uint64 The time to be checked + * @param start uint64 A time representing the begining of the grant + * @param cliff uint64 The cliff period. + * @param vesting uint64 The vesting period. + * @return An uint256 representing the amount of vested tokensof a specif grant. + * transferableTokens + * | _/-------- vestedTokens rect + * | _/ + * | _/ + * | _/ + * | _/ + * | / + * | .| + * | . | + * | . | + * | . | + * | . | + * | . | + * +===+===========+---------+----------> time + * Start Clift Vesting + */ + function calculateVestedTokens( + uint256 tokens, + uint256 time, + uint256 start, + uint256 cliff, + uint256 vesting) constant returns (uint256) + { + // Shortcuts for before cliff and after vesting cases. + if (time < cliff) return 0; + if (time >= vesting) return tokens; + + // Interpolate all vested tokens. + // As before cliff the shortcut returns 0, we can use just calculate a value + // in the vesting rect (as shown in above's figure) + + // vestedTokens = tokens * (time - start) / (vesting - start) + uint256 vestedTokens = SafeMath.div( + SafeMath.mul( + tokens, + SafeMath.sub(time, start) + ), + SafeMath.sub(vesting, start) + ); + + return vestedTokens; + } + + /** + * @dev Get all information about a specifc grant. + * @param _holder The address which will have its tokens revoked. + * @param _grantId The id of the token grant. + * @return Returns all the values that represent a TokenGrant(address, value, start, cliff, + * revokability, burnsOnRevoke, and vesting) plus the vested value at the current time. + */ + function tokenGrant(address _holder, uint256 _grantId) constant returns (address granter, uint256 value, uint256 vested, uint64 start, uint64 cliff, uint64 vesting, bool revokable, bool burnsOnRevoke) { + TokenGrant grant = grants[_holder][_grantId]; + + granter = grant.granter; + value = grant.value; + start = grant.start; + cliff = grant.cliff; + vesting = grant.vesting; + revokable = grant.revokable; + burnsOnRevoke = grant.burnsOnRevoke; + + vested = vestedTokens(grant, uint64(now)); + } + + /** + * @dev Get the amount of vested tokens at a specific time. + * @param grant TokenGrant The grant to be checked. + * @param time The time to be checked + * @return An uint256 representing the amount of vested tokens of a specific grant at a specific time. + */ + function vestedTokens(TokenGrant grant, uint64 time) private constant returns (uint256) { + return calculateVestedTokens( + grant.value, + uint256(time), + uint256(grant.start), + uint256(grant.cliff), + uint256(grant.vesting) + ); + } + + /** + * @dev Calculate the amount of non vested tokens at a specific time. + * @param grant TokenGrant The grant to be checked. + * @param time uint64 The time to be checked + * @return An uint256 representing the amount of non vested tokens of a specifc grant on the + * passed time frame. + */ + function nonVestedTokens(TokenGrant grant, uint64 time) private constant returns (uint256) { + return grant.value.sub(vestedTokens(grant, time)); + } + + /** + * @dev Calculate the date when the holder can trasfer all its tokens + * @param holder address The address of the holder + * @return An uint256 representing the date of the last transferable tokens. + */ + function lastTokenIsTransferableDate(address holder) constant public returns (uint64 date) { + date = uint64(now); + uint256 grantIndex = grants[holder].length; + for (uint256 i = 0; i < grantIndex; i++) { + date = Math.max64(grants[holder][i].vesting, date); + } + } +} |