30 lines
1017 B
Solidity
30 lines
1017 B
Solidity
pragma solidity ^0.4.24;
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/**
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* Utility library of inline functions on addresses
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*/
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library AddressUtils {
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/**
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* Returns whether the target address is a contract
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* @dev This function will return false if invoked during the constructor of a contract,
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* as the code is not actually created until after the constructor finishes.
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* @param addr address to check
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* @return whether the target address is a contract
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*/
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function isContract(address addr) internal view returns (bool) {
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uint256 size;
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// XXX Currently there is no better way to check if there is a contract in an address
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// than to check the size of the code at that address.
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// See https://ethereum.stackexchange.com/a/14016/36603
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// for more details about how this works.
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// TODO Check this again before the Serenity release, because all addresses will be
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// contracts then.
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// solium-disable-next-line security/no-inline-assembly
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assembly { size := extcodesize(addr) }
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return size > 0;
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}
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}
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