Bytes

Git Source

Author: Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Bytes.sol)

Bytes operations.

Functions

indexOf

Forward search for s in buffer

If s is present in the buffer, returns the index of the first instance

If s is not present in the buffer, returns type(uint256).max

NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf[Javascript's Array.indexOf]

function indexOf(bytes memory buffer, bytes1 s) internal pure returns (uint256);

Parameters

Name	Type	Description
buffer	`bytes`
s	`bytes1`

Returns

Name	Type	Description
<none>	`uint256`

indexOf

Forward search for s in buffer starting at position pos

If s is present in the buffer (at or after pos), returns the index of the next instance

If s is not present in the buffer (at or after pos), returns type(uint256).max

NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf[Javascript's Array.indexOf]

function indexOf(bytes memory buffer, bytes1 s, uint256 pos) internal pure returns (uint256);

Parameters

Name	Type	Description
buffer	`bytes`
s	`bytes1`
pos	`uint256`

Returns

Name	Type	Description
<none>	`uint256`

lastIndexOf

Backward search for s in buffer

If s is present in the buffer, returns the index of the last instance

If s is not present in the buffer, returns type(uint256).max

NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/lastIndexOf[Javascript's Array.lastIndexOf]

function lastIndexOf(bytes memory buffer, bytes1 s) internal pure returns (uint256);

Parameters

Name	Type	Description
buffer	`bytes`
s	`bytes1`

Returns

Name	Type	Description
<none>	`uint256`

lastIndexOf

Backward search for s in buffer starting at position pos

If s is present in the buffer (at or before pos), returns the index of the previous instance

If s is not present in the buffer (at or before pos), returns type(uint256).max

NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/lastIndexOf[Javascript's Array.lastIndexOf]

function lastIndexOf(bytes memory buffer, bytes1 s, uint256 pos) internal pure returns (uint256);

Parameters

Name	Type	Description
buffer	`bytes`
s	`bytes1`
pos	`uint256`

Returns

Name	Type	Description
<none>	`uint256`

slice

Copies the content of buffer, from start (included) to the end of buffer into a new bytes object in memory.
NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's Array.slice]

function slice(bytes memory buffer, uint256 start) internal pure returns (bytes memory);

Parameters

Name	Type	Description
buffer	`bytes`
start	`uint256`

Returns

Name	Type	Description
<none>	`bytes`

slice

Copies the content of buffer, from start (included) to end (excluded) into a new bytes object in memory. The end argument is truncated to the length of the buffer.
NOTE: replicates the behavior of https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice[Javascript's Array.slice]

function slice(bytes memory buffer, uint256 start, uint256 end) internal pure returns (bytes memory);

Parameters

Name	Type	Description
buffer	`bytes`
start	`uint256`
end	`uint256`

Returns

Name	Type	Description
<none>	`bytes`

splice

Moves the content of buffer, from start (included) to the end of buffer to the start of that buffer, and shrinks the buffer length accordingly, effectively overriding the content of buffer with buffer[start:].
NOTE: This function modifies the provided buffer in place. If you need to preserve the original buffer, use slice instead

function splice(bytes memory buffer, uint256 start) internal pure returns (bytes memory);

Parameters

Name	Type	Description
buffer	`bytes`
start	`uint256`

Returns

Name	Type	Description
<none>	`bytes`

splice

Moves the content of buffer, from start (included) to end (excluded) to the start of that buffer, and shrinks the buffer length accordingly, effectively overriding the content of buffer with buffer[start:end]. The end argument is truncated to the length of the buffer.
NOTE: This function modifies the provided buffer in place. If you need to preserve the original buffer, use slice instead

function splice(bytes memory buffer, uint256 start, uint256 end) internal pure returns (bytes memory);

Parameters

Name	Type	Description
buffer	`bytes`
start	`uint256`
end	`uint256`

Returns

Name	Type	Description
<none>	`bytes`

replace

Replaces bytes in buffer starting at pos with all bytes from replacement.
Parameters are clamped to valid ranges (i.e. pos is clamped to [0, buffer.length]). If pos >= buffer.length, no replacement occurs and the buffer is returned unchanged.
NOTE: This function modifies the provided buffer in place.

function replace(bytes memory buffer, uint256 pos, bytes memory replacement) internal pure returns (bytes memory);

Parameters

Name	Type	Description
buffer	`bytes`
pos	`uint256`
replacement	`bytes`

Returns

Name	Type	Description
<none>	`bytes`

replace

Replaces bytes in buffer starting at pos with bytes from replacement starting at offset. Copies at most length bytes from replacement to buffer.
Parameters are clamped to valid ranges (i.e. pos is clamped to [0, buffer.length], offset is clamped to [0, replacement.length], and length is clamped to min(length, replacement.length - offset, buffer.length - pos)). If pos >= buffer.length or offset >= replacement.length, no replacement occurs and the buffer is returned unchanged.
NOTE: This function modifies the provided buffer in place.

function replace(bytes memory buffer, uint256 pos, bytes memory replacement, uint256 offset, uint256 length)
        internal
        pure
        returns (bytes memory);

Parameters

Name	Type	Description
buffer	`bytes`
pos	`uint256`
replacement	`bytes`
offset	`uint256`
length	`uint256`

Returns

Name	Type	Description
<none>	`bytes`

concat

Concatenate an array of bytes into a single bytes object.
For fixed bytes types, we recommend using the solidity built-in bytes.concat or (equivalent) abi.encodePacked.
NOTE: this could be done in assembly with a single loop that expands starting at the FMP, but that would be significantly less readable. It might be worth benchmarking the savings of the full-assembly approach.

function concat(bytes[] memory buffers) internal pure returns (bytes memory);

Parameters

Name	Type	Description
buffers	`bytes[]`

Returns

Name	Type	Description
<none>	`bytes`

toNibbles

Split each byte in input into two nibbles (4 bits each)
Example: hex"01234567" → hex"0001020304050607"

function toNibbles(bytes memory input) internal pure returns (bytes memory output);

Parameters

Name	Type	Description
input	`bytes`

Returns

Name	Type	Description
output	`bytes`

equal

Returns true if the two byte buffers are equal.

function equal(bytes memory a, bytes memory b) internal pure returns (bool);

Parameters

Name	Type	Description
a	`bytes`
b	`bytes`

Returns

Name	Type	Description
<none>	`bool`

reverseBytes32

Reverses the byte order of a bytes32 value, converting between little-endian and big-endian. Inspired by https://graphics.stanford.edu/~seander/bithacks.html#ReverseParallel[Reverse Parallel]

function reverseBytes32(bytes32 value) internal pure returns (bytes32);

Parameters

Name	Type	Description
value	`bytes32`

Returns

Name	Type	Description
<none>	`bytes32`

reverseBytes16

Same as reverseBytes32 but optimized for 128-bit values.

function reverseBytes16(bytes16 value) internal pure returns (bytes16);

Parameters

Name	Type	Description
value	`bytes16`

Returns

Name	Type	Description
<none>	`bytes16`

reverseBytes8

Same as reverseBytes32 but optimized for 64-bit values.

function reverseBytes8(bytes8 value) internal pure returns (bytes8);

Parameters

Name	Type	Description
value	`bytes8`

Returns

Name	Type	Description
<none>	`bytes8`

reverseBytes4

Same as reverseBytes32 but optimized for 32-bit values.

function reverseBytes4(bytes4 value) internal pure returns (bytes4);

Parameters

Name	Type	Description
value	`bytes4`

Returns

Name	Type	Description
<none>	`bytes4`

reverseBytes2

Same as reverseBytes32 but optimized for 16-bit values.

function reverseBytes2(bytes2 value) internal pure returns (bytes2);

Parameters

Name	Type	Description
value	`bytes2`

Returns

Name	Type	Description
<none>	`bytes2`

clz

Counts the number of leading zero bits a bytes array. Returns 8 * buffer.length if the buffer is all zeros.

function clz(bytes memory buffer) internal pure returns (uint256);

Parameters

Name	Type	Description
buffer	`bytes`

Returns

Name	Type	Description
<none>	`uint256`

_unsafeReadBytesOffset

Reads a bytes32 from a bytes array without bounds checking.
NOTE: making this function internal would mean it could be used with memory unsafe offset, and marking the assembly block as such would prevent some optimizations.

function _unsafeReadBytesOffset(bytes memory buffer, uint256 offset) private pure returns (bytes32 value);

Parameters

Name	Type	Description
buffer	`bytes`
offset	`uint256`

Returns

Name	Type	Description
value	`bytes32`