You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
248 lines
8.2 KiB
248 lines
8.2 KiB
const format = require('../format-lines');
|
|
const { OPTS } = require('./Checkpoints.opts');
|
|
|
|
// TEMPLATE
|
|
const header = `\
|
|
pragma solidity ^0.8.20;
|
|
|
|
import {Math} from "../math/Math.sol";
|
|
|
|
/**
|
|
* @dev This library defines the \`Trace*\` struct, for checkpointing values as they change at different points in
|
|
* time, and later looking up past values by block number. See {Votes} as an example.
|
|
*
|
|
* To create a history of checkpoints define a variable type \`Checkpoints.Trace*\` in your contract, and store a new
|
|
* checkpoint for the current transaction block using the {push} function.
|
|
*/
|
|
`;
|
|
|
|
const errors = `\
|
|
/**
|
|
* @dev A value was attempted to be inserted on a past checkpoint.
|
|
*/
|
|
error CheckpointUnorderedInsertion();
|
|
`;
|
|
|
|
const template = opts => `\
|
|
struct ${opts.historyTypeName} {
|
|
${opts.checkpointTypeName}[] ${opts.checkpointFieldName};
|
|
}
|
|
|
|
struct ${opts.checkpointTypeName} {
|
|
${opts.keyTypeName} ${opts.keyFieldName};
|
|
${opts.valueTypeName} ${opts.valueFieldName};
|
|
}
|
|
|
|
/**
|
|
* @dev Pushes a (\`key\`, \`value\`) pair into a ${opts.historyTypeName} so that it is stored as the checkpoint.
|
|
*
|
|
* Returns previous value and new value.
|
|
*
|
|
* IMPORTANT: Never accept \`key\` as a user input, since an arbitrary \`type(${opts.keyTypeName}).max\` key set will disable the
|
|
* library.
|
|
*/
|
|
function push(
|
|
${opts.historyTypeName} storage self,
|
|
${opts.keyTypeName} key,
|
|
${opts.valueTypeName} value
|
|
) internal returns (${opts.valueTypeName}, ${opts.valueTypeName}) {
|
|
return _insert(self.${opts.checkpointFieldName}, key, value);
|
|
}
|
|
|
|
/**
|
|
* @dev Returns the value in the first (oldest) checkpoint with key greater or equal than the search key, or zero if
|
|
* there is none.
|
|
*/
|
|
function lowerLookup(${opts.historyTypeName} storage self, ${opts.keyTypeName} key) internal view returns (${opts.valueTypeName}) {
|
|
uint256 len = self.${opts.checkpointFieldName}.length;
|
|
uint256 pos = _lowerBinaryLookup(self.${opts.checkpointFieldName}, key, 0, len);
|
|
return pos == len ? 0 : _unsafeAccess(self.${opts.checkpointFieldName}, pos).${opts.valueFieldName};
|
|
}
|
|
|
|
/**
|
|
* @dev Returns the value in the last (most recent) checkpoint with key lower or equal than the search key, or zero
|
|
* if there is none.
|
|
*/
|
|
function upperLookup(${opts.historyTypeName} storage self, ${opts.keyTypeName} key) internal view returns (${opts.valueTypeName}) {
|
|
uint256 len = self.${opts.checkpointFieldName}.length;
|
|
uint256 pos = _upperBinaryLookup(self.${opts.checkpointFieldName}, key, 0, len);
|
|
return pos == 0 ? 0 : _unsafeAccess(self.${opts.checkpointFieldName}, pos - 1).${opts.valueFieldName};
|
|
}
|
|
|
|
/**
|
|
* @dev Returns the value in the last (most recent) checkpoint with key lower or equal than the search key, or zero
|
|
* if there is none.
|
|
*
|
|
* NOTE: This is a variant of {upperLookup} that is optimised to find "recent" checkpoint (checkpoints with high
|
|
* keys).
|
|
*/
|
|
function upperLookupRecent(${opts.historyTypeName} storage self, ${opts.keyTypeName} key) internal view returns (${opts.valueTypeName}) {
|
|
uint256 len = self.${opts.checkpointFieldName}.length;
|
|
|
|
uint256 low = 0;
|
|
uint256 high = len;
|
|
|
|
if (len > 5) {
|
|
uint256 mid = len - Math.sqrt(len);
|
|
if (key < _unsafeAccess(self.${opts.checkpointFieldName}, mid)._key) {
|
|
high = mid;
|
|
} else {
|
|
low = mid + 1;
|
|
}
|
|
}
|
|
|
|
uint256 pos = _upperBinaryLookup(self.${opts.checkpointFieldName}, key, low, high);
|
|
|
|
return pos == 0 ? 0 : _unsafeAccess(self.${opts.checkpointFieldName}, pos - 1).${opts.valueFieldName};
|
|
}
|
|
|
|
/**
|
|
* @dev Returns the value in the most recent checkpoint, or zero if there are no checkpoints.
|
|
*/
|
|
function latest(${opts.historyTypeName} storage self) internal view returns (${opts.valueTypeName}) {
|
|
uint256 pos = self.${opts.checkpointFieldName}.length;
|
|
return pos == 0 ? 0 : _unsafeAccess(self.${opts.checkpointFieldName}, pos - 1).${opts.valueFieldName};
|
|
}
|
|
|
|
/**
|
|
* @dev Returns whether there is a checkpoint in the structure (i.e. it is not empty), and if so the key and value
|
|
* in the most recent checkpoint.
|
|
*/
|
|
function latestCheckpoint(${opts.historyTypeName} storage self)
|
|
internal
|
|
view
|
|
returns (
|
|
bool exists,
|
|
${opts.keyTypeName} ${opts.keyFieldName},
|
|
${opts.valueTypeName} ${opts.valueFieldName}
|
|
)
|
|
{
|
|
uint256 pos = self.${opts.checkpointFieldName}.length;
|
|
if (pos == 0) {
|
|
return (false, 0, 0);
|
|
} else {
|
|
${opts.checkpointTypeName} storage ckpt = _unsafeAccess(self.${opts.checkpointFieldName}, pos - 1);
|
|
return (true, ckpt.${opts.keyFieldName}, ckpt.${opts.valueFieldName});
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @dev Returns the number of checkpoint.
|
|
*/
|
|
function length(${opts.historyTypeName} storage self) internal view returns (uint256) {
|
|
return self.${opts.checkpointFieldName}.length;
|
|
}
|
|
|
|
/**
|
|
* @dev Returns checkpoint at given position.
|
|
*/
|
|
function at(${opts.historyTypeName} storage self, uint32 pos) internal view returns (${opts.checkpointTypeName} memory) {
|
|
return self.${opts.checkpointFieldName}[pos];
|
|
}
|
|
|
|
/**
|
|
* @dev Pushes a (\`key\`, \`value\`) pair into an ordered list of checkpoints, either by inserting a new checkpoint,
|
|
* or by updating the last one.
|
|
*/
|
|
function _insert(
|
|
${opts.checkpointTypeName}[] storage self,
|
|
${opts.keyTypeName} key,
|
|
${opts.valueTypeName} value
|
|
) private returns (${opts.valueTypeName}, ${opts.valueTypeName}) {
|
|
uint256 pos = self.length;
|
|
|
|
if (pos > 0) {
|
|
${opts.checkpointTypeName} storage last = _unsafeAccess(self, pos - 1);
|
|
${opts.keyTypeName} lastKey = last.${opts.keyFieldName};
|
|
${opts.valueTypeName} lastValue = last.${opts.valueFieldName};
|
|
|
|
// Checkpoint keys must be non-decreasing.
|
|
if (lastKey > key) {
|
|
revert CheckpointUnorderedInsertion();
|
|
}
|
|
|
|
// Update or push new checkpoint
|
|
if (lastKey == key) {
|
|
_unsafeAccess(self, pos - 1).${opts.valueFieldName} = value;
|
|
} else {
|
|
self.push(${opts.checkpointTypeName}({${opts.keyFieldName}: key, ${opts.valueFieldName}: value}));
|
|
}
|
|
return (lastValue, value);
|
|
} else {
|
|
self.push(${opts.checkpointTypeName}({${opts.keyFieldName}: key, ${opts.valueFieldName}: value}));
|
|
return (0, value);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @dev Return the index of the last (most recent) checkpoint with key lower or equal than the search key, or \`high\`
|
|
* if there is none. \`low\` and \`high\` define a section where to do the search, with inclusive \`low\` and exclusive
|
|
* \`high\`.
|
|
*
|
|
* WARNING: \`high\` should not be greater than the array's length.
|
|
*/
|
|
function _upperBinaryLookup(
|
|
${opts.checkpointTypeName}[] storage self,
|
|
${opts.keyTypeName} key,
|
|
uint256 low,
|
|
uint256 high
|
|
) private view returns (uint256) {
|
|
while (low < high) {
|
|
uint256 mid = Math.average(low, high);
|
|
if (_unsafeAccess(self, mid).${opts.keyFieldName} > key) {
|
|
high = mid;
|
|
} else {
|
|
low = mid + 1;
|
|
}
|
|
}
|
|
return high;
|
|
}
|
|
|
|
/**
|
|
* @dev Return the index of the first (oldest) checkpoint with key is greater or equal than the search key, or
|
|
* \`high\` if there is none. \`low\` and \`high\` define a section where to do the search, with inclusive \`low\` and
|
|
* exclusive \`high\`.
|
|
*
|
|
* WARNING: \`high\` should not be greater than the array's length.
|
|
*/
|
|
function _lowerBinaryLookup(
|
|
${opts.checkpointTypeName}[] storage self,
|
|
${opts.keyTypeName} key,
|
|
uint256 low,
|
|
uint256 high
|
|
) private view returns (uint256) {
|
|
while (low < high) {
|
|
uint256 mid = Math.average(low, high);
|
|
if (_unsafeAccess(self, mid).${opts.keyFieldName} < key) {
|
|
low = mid + 1;
|
|
} else {
|
|
high = mid;
|
|
}
|
|
}
|
|
return high;
|
|
}
|
|
|
|
/**
|
|
* @dev Access an element of the array without performing bounds check. The position is assumed to be within bounds.
|
|
*/
|
|
function _unsafeAccess(${opts.checkpointTypeName}[] storage self, uint256 pos)
|
|
private
|
|
pure
|
|
returns (${opts.checkpointTypeName} storage result)
|
|
{
|
|
assembly {
|
|
mstore(0, self.slot)
|
|
result.slot := add(keccak256(0, 0x20), pos)
|
|
}
|
|
}
|
|
`;
|
|
/* eslint-enable max-len */
|
|
|
|
// GENERATE
|
|
module.exports = format(
|
|
header.trimEnd(),
|
|
'library Checkpoints {',
|
|
errors,
|
|
OPTS.flatMap(opts => template(opts)),
|
|
'}',
|
|
);
|
|
|