// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;
/// @notice Read and write to persistent storage at a fraction of the cost.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SSTORE2.sol)
/// @author Modified from 0xSequence (https://github.com/0xSequence/sstore2/blob/master/contracts/SSTORE2.sol)
library SSTORE2 {
uint256 internal constant DATA_OFFSET = 1; // We skip the first byte as it's a STOP opcode to ensure the contract can't be called.
/*//////////////////////////////////////////////////////////////
WRITE LOGIC
//////////////////////////////////////////////////////////////*/
function write(bytes memory data) internal returns (address pointer) {
// Prefix the bytecode with a STOP opcode to ensure it cannot be called.
bytes memory runtimeCode = abi.encodePacked(hex"00", data);
bytes memory creationCode = abi.encodePacked(
//---------------------------------------------------------------------------------------------------------------//
// Opcode | Opcode + Arguments | Description | Stack View //
//---------------------------------------------------------------------------------------------------------------//
// 0x60 | 0x600B | PUSH1 11 | codeOffset //
// 0x59 | 0x59 | MSIZE | 0 codeOffset //
// 0x81 | 0x81 | DUP2 | codeOffset 0 codeOffset //
// 0x38 | 0x38 | CODESIZE | codeSize codeOffset 0 codeOffset //
// 0x03 | 0x03 | SUB | (codeSize - codeOffset) 0 codeOffset //
// 0x80 | 0x80 | DUP | (codeSize - codeOffset) (codeSize - codeOffset) 0 codeOffset //
// 0x92 | 0x92 | SWAP3 | codeOffset (codeSize - codeOffset) 0 (codeSize - codeOffset) //
// 0x59 | 0x59 | MSIZE | 0 codeOffset (codeSize - codeOffset) 0 (codeSize - codeOffset) //
// 0x39 | 0x39 | CODECOPY | 0 (codeSize - codeOffset) //
// 0xf3 | 0xf3 | RETURN | //
//---------------------------------------------------------------------------------------------------------------//
hex"60_0B_59_81_38_03_80_92_59_39_F3", // Returns all code in the contract except for the first 11 (0B in hex) bytes.
runtimeCode // The bytecode we want the contract to have after deployment. Capped at 1 byte less than the code size limit.
);
assembly {
// Deploy a new contract with the generated creation code.
// We start 32 bytes into the code to avoid copying the byte length.
pointer := create(0, add(creationCode, 32), mload(creationCode))
}
require(pointer != address(0), "DEPLOYMENT_FAILED");
}
/*//////////////////////////////////////////////////////////////
READ LOGIC
//////////////////////////////////////////////////////////////*/
function read(address pointer) internal view returns (bytes memory) {
return readBytecode(pointer, DATA_OFFSET, pointer.code.length - DATA_OFFSET);
}
function read(address pointer, uint256 start) internal view returns (bytes memory) {
start += DATA_OFFSET;
return readBytecode(pointer, start, pointer.code.length - start);
}
function read(
address pointer,
uint256 start,
uint256 end
) internal view returns (bytes memory) {
start += DATA_OFFSET;
end += DATA_OFFSET;
require(pointer.code.length >= end, "OUT_OF_BOUNDS");
return readBytecode(pointer, start, end - start);
}
/*//////////////////////////////////////////////////////////////
INTERNAL HELPER LOGIC
//////////////////////////////////////////////////////////////*/
function readBytecode(
address pointer,
uint256 start,
uint256 size
) private view returns (bytes memory data) {
assembly {
// Get a pointer to some free memory.
data := mload(0x40)
// Update the free memory pointer to prevent overriding our data.
// We use and(x, not(31)) as a cheaper equivalent to sub(x, mod(x, 32)).
// Adding 31 to size and running the result through the logic above ensures
// the memory pointer remains word-aligned, following the Solidity convention.
mstore(0x40, add(data, and(add(add(size, 32), 31), not(31))))
// Store the size of the data in the first 32 byte chunk of free memory.
mstore(data, size)
// Copy the code into memory right after the 32 bytes we used to store the size.
extcodecopy(pointer, add(data, 32), start, size)
}
}
}