22 lines
633 B
Solidity
22 lines
633 B
Solidity
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pragma solidity ^0.4.24;
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import "./Initializable.sol";
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contract Petrifiable is Initializable {
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// Use block UINT256_MAX (which should be never) as the initializable date
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uint256 internal constant PETRIFIED_BLOCK = uint256(-1);
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function isPetrified() public view returns (bool) {
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return getInitializationBlock() == PETRIFIED_BLOCK;
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}
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/**
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* @dev Function to be called by top level contract to prevent being initialized.
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* Useful for freezing base contracts when they're used behind proxies.
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*/
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function petrify() internal onlyInit {
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initializedAt(PETRIFIED_BLOCK);
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}
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}
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