@ -15,39 +15,39 @@ import {Math} from "./math/Math.sol";
` ;
` ;
const sort = type => ` \
const sort = type => ` \
/ * * / * *
* @ dev Sort an array of $ { type } ( in memory ) following the provided comparator function . * @ dev Sort an array of $ { type } ( in memory ) following the provided comparator function .
* *
* This function does the sorting "in place" , meaning that it overrides the input . The object is returned for * This function does the sorting "in place" , meaning that it overrides the input . The object is returned for
* convenience , but that returned value can be discarded safely if the caller has a memory pointer to the array . * convenience , but that returned value can be discarded safely if the caller has a memory pointer to the array .
* *
* NOTE : this function ' s cost is \ ` O(n · log(n)) \` in average and \` O(n²) \` in the worst case, with n the length of the
* NOTE : this function ' s cost is \ ` O(n · log(n)) \` in average and \` O(n²) \` in the worst case, with n the length of the
* array . Using it in view functions that are executed through \ ` eth_call \` is safe, but one should be very careful
* array . Using it in view functions that are executed through \ ` eth_call \` is safe, but one should be very careful
* when executing this as part of a transaction . If the array being sorted is too large , the sort operation may * when executing this as part of a transaction . If the array being sorted is too large , the sort operation may
* consume more gas than is available in a block , leading to potential DoS . * consume more gas than is available in a block , leading to potential DoS .
* / * /
function sort ( function sort (
$ { type } [ ] memory array , $ { type } [ ] memory array ,
function ( $ { type } , $ { type } ) pure returns ( bool ) comp function ( $ { type } , $ { type } ) pure returns ( bool ) comp
) internal pure returns ( $ { type } [ ] memory ) { ) internal pure returns ( $ { type } [ ] memory ) {
$ { $ {
type === 'bytes32' type === 'bytes32'
? '_quickSort(_begin(array), _end(array), comp);' ? '_quickSort(_begin(array), _end(array), comp);'
: 'sort(_castToBytes32Array(array), _castToBytes32Comp(comp));' : 'sort(_castToBytes32Array(array), _castToBytes32Comp(comp));'
}
return array ;
} }
return array ;
}
/ * * / * *
* @ dev Variant of { sort } that sorts an array of $ { type } in increasing order . * @ dev Variant of { sort } that sorts an array of $ { type } in increasing order .
* / * /
function sort ( $ { type } [ ] memory array ) internal pure returns ( $ { type } [ ] memory ) { function sort ( $ { type } [ ] memory array ) internal pure returns ( $ { type } [ ] memory ) {
$ { type === 'bytes32' ? 'sort(array, _defaultComp);' : 'sort(_castToBytes32Array(array), _defaultComp);' } $ { type === 'bytes32' ? 'sort(array, _defaultComp);' : 'sort(_castToBytes32Array(array), _defaultComp);' }
return array ; return array ;
} }
` ;
` ;
const quickSort = ` const quickSort = ` \
/ * * / * *
* @ dev Performs a quick sort of a segment of memory . The segment sorted starts at \ ` begin \` (inclusive), and stops
* @ dev Performs a quick sort of a segment of memory . The segment sorted starts at \ ` begin \` (inclusive), and stops
* at end ( exclusive ) . Sorting follows the \ ` comp \` comparator.
* at end ( exclusive ) . Sorting follows the \ ` comp \` comparator.
@ -123,34 +123,34 @@ function _swap(uint256 ptr1, uint256 ptr2) private pure {
} }
` ;
` ;
const defaultComparator = ` const defaultComparator = ` \
/// @dev Comparator for sorting arrays in increasing order.
/// @dev Comparator for sorting arrays in increasing order.
function _defaultComp ( bytes32 a , bytes32 b ) private pure returns ( bool ) { function _defaultComp ( bytes32 a , bytes32 b ) private pure returns ( bool ) {
return a < b ; return a < b ;
} }
` ;
` ;
const castArray = type => ` \
const castArray = type => ` \
/// @dev Helper: low level cast ${type} memory array to uint256 memory array
/// @dev Helper: low level cast ${type} memory array to uint256 memory array
function _castToBytes32Array ( $ { type } [ ] memory input ) private pure returns ( bytes32 [ ] memory output ) { function _castToBytes32Array ( $ { type } [ ] memory input ) private pure returns ( bytes32 [ ] memory output ) {
assembly { assembly {
output : = input output : = input
}
} }
}
` ;
` ;
const castComparator = type => ` \
const castComparator = type => ` \
/// @dev Helper: low level cast ${type} comp function to bytes32 comp function
/// @dev Helper: low level cast ${type} comp function to bytes32 comp function
function _castToBytes32Comp ( function _castToBytes32Comp (
function ( $ { type } , $ { type } ) pure returns ( bool ) input function ( $ { type } , $ { type } ) pure returns ( bool ) input
) private pure returns ( function ( bytes32 , bytes32 ) pure returns ( bool ) output ) { ) private pure returns ( function ( bytes32 , bytes32 ) pure returns ( bool ) output ) {
assembly { assembly {
output : = input output : = input
}
} }
}
` ;
` ;
const search = ` const search = ` \
/ * * / * *
* @ dev Searches a sorted \ ` array \` and returns the first index that contains
* @ dev Searches a sorted \ ` array \` and returns the first index that contains
* a value greater or equal to \ ` element \` . If no such index exists (i.e. all
* a value greater or equal to \ ` element \` . If no such index exists (i.e. all
@ -319,12 +319,12 @@ function upperBoundMemory(uint256[] memory array, uint256 element) internal pure
} }
` ;
` ;
const unsafeAccessStorage = type => ` const unsafeAccessStorage = type => ` \
/ * * / * *
* @ dev Access an array in an "unsafe" way . Skips solidity "index-out-of-range" check . * @ dev Access an array in an "unsafe" way . Skips solidity "index-out-of-range" check .
* *
* WARNING : Only use if you are certain \ ` pos \` is lower than the array length.
* WARNING : Only use if you are certain \ ` pos \` is lower than the array length.
* / * /
function unsafeAccess ( $ { type } [ ] storage arr , uint256 pos ) internal pure returns ( StorageSlot . $ { capitalize ( function unsafeAccess ( $ { type } [ ] storage arr , uint256 pos ) internal pure returns ( StorageSlot . $ { capitalize (
type , type ,
) } Slot storage ) { ) } Slot storage ) {
@ -334,9 +334,10 @@ function unsafeAccess(${type}[] storage arr, uint256 pos) internal pure returns
slot : = arr . slot slot : = arr . slot
} }
return slot . deriveArray ( ) . offset ( pos ) . get$ { capitalize ( type ) } Slot ( ) ; return slot . deriveArray ( ) . offset ( pos ) . get$ { capitalize ( type ) } Slot ( ) ;
} ` ;
}
` ;
const unsafeAccessMemory = type => ` const unsafeAccessMemory = type => ` \
/ * * / * *
* @ dev Access an array in an "unsafe" way . Skips solidity "index-out-of-range" check . * @ dev Access an array in an "unsafe" way . Skips solidity "index-out-of-range" check .
* *
@ -349,7 +350,7 @@ function unsafeMemoryAccess(${type}[] memory arr, uint256 pos) internal pure ret
} }
` ;
` ;
const unsafeSetLength = type => ` const unsafeSetLength = type => ` \
/ * * / * *
* @ dev Helper to set the length of an dynamic array . Directly writing to \ ` .length \` is forbidden.
* @ dev Helper to set the length of an dynamic array . Directly writing to \ ` .length \` is forbidden.
* *
@ -360,26 +361,32 @@ function unsafeSetLength(${type}[] storage array, uint256 len) internal {
assembly { assembly {
sstore ( array . slot , len ) sstore ( array . slot , len )
} }
} ` ;
}
` ;
// GENERATE
// GENERATE
module . exports = format ( module . exports = format (
header . trimEnd ( ) , header . trimEnd ( ) ,
'library Arrays {' , 'library Arrays {' ,
'using SlotDerivation for bytes32;' , format (
'using StorageSlot for bytes32;' , [ ] . concat (
// sorting, comparator, helpers and internal
'using SlotDerivation for bytes32;' ,
sort ( 'bytes32' ) , 'using StorageSlot for bytes32;' ,
TYPES . filter ( type => type !== 'bytes32' ) . map ( sort ) , '' ,
quickSort , // sorting, comparator, helpers and internal
defaultComparator , sort ( 'bytes32' ) ,
TYPES . filter ( type => type !== 'bytes32' ) . map ( castArray ) , TYPES . filter ( type => type !== 'bytes32' ) . map ( sort ) ,
TYPES . filter ( type => type !== 'bytes32' ) . map ( castComparator ) , quickSort ,
// lookup
defaultComparator ,
search , TYPES . filter ( type => type !== 'bytes32' ) . map ( castArray ) ,
// unsafe (direct) storage and memory access
TYPES . filter ( type => type !== 'bytes32' ) . map ( castComparator ) ,
TYPES . map ( unsafeAccessStorage ) , // lookup
TYPES . map ( unsafeAccessMemory ) , search ,
TYPES . map ( unsafeSetLength ) , // unsafe (direct) storage and memory access
TYPES . map ( unsafeAccessStorage ) ,
TYPES . map ( unsafeAccessMemory ) ,
TYPES . map ( unsafeSetLength ) ,
) ,
) . trimEnd ( ) ,
'}' , '}' ,
) ; ) ;
Hadrien Croubois
8 months ago
committed by
GitHub