snt-gas-relay/contracts/deploy/Factory.sol

100 lines
2.7 KiB
Solidity

pragma solidity ^0.4.17;
import "../common/Controlled.sol";
contract Factory is Controlled {
event NewKernel(address newKernel, bytes32 codeHash);
struct Version {
uint256 blockNumber;
uint256 timestamp;
address kernel;
bytes32 codeHash;
}
mapping(bytes32 => uint256) hashToVersion;
mapping(address => uint256) versionMap;
Version[] versionLog;
uint256 latestUpdate;
address latestKernel;
function Factory(address _kernel)
public
{
_setKernel(_kernel);
}
function setKernel(address _kernel)
external
onlyController
{
_setKernel(_kernel);
}
function getVersion(uint256 index)
public
view
returns(
uint256 blockNumber,
uint256 timestamp,
address kernel,
bytes32 codeHash
)
{
return (
versionLog[index].blockNumber,
versionLog[index].timestamp,
versionLog[index].kernel,
versionLog[index].codeHash
);
}
function isKernel(bytes32 _codeHash) public view returns (bool){
return hashToVersion[_codeHash] > 0;
}
function isKernel(address _addr) public view returns (bool){
return versionMap[_addr] > 0;
}
function getCodeHash(address _addr)
public
view
returns (bytes32 codeHash)
{
bytes memory o_code;
uint size;
assembly {
// retrieve the size of the code, this needs assembly
size := extcodesize(_addr)
}
require (size > 0);
assembly {
// allocate output byte array - this could also be done without assembly
// by using o_code = new bytes(size)
o_code := mload(0x40)
// new "memory end" including padding
mstore(0x40, add(o_code, and(add(add(size, 0x20), 0x1f), not(0x1f))))
// store length in memory
mstore(o_code, size)
// actually retrieve the code, this needs assembly
extcodecopy(_addr, add(o_code, 0x20), 0, size)
}
codeHash = keccak256(o_code);
}
function _setKernel(address _kernel)
internal
{
require(_kernel != latestKernel);
bytes32 _codeHash = getCodeHash(_kernel);
versionMap[_kernel] = versionLog.length;
hashToVersion[_codeHash] = versionLog.length;
versionLog.push(Version({blockNumber: block.number, timestamp: block.timestamp, kernel: _kernel, codeHash: _codeHash}));
latestUpdate = block.timestamp;
latestKernel = _kernel;
emit NewKernel(_kernel, _codeHash);
}
}