vortex_buffer/bit/
mod.rs

1// SPDX-License-Identifier: Apache-2.0
2// SPDX-FileCopyrightText: Copyright the Vortex contributors
3
4//! Packed bitmaps that can be used to store boolean values.
5//!
6//! This module provides a wrapper on top of the `Buffer` type to store mutable and immutable
7//! bitsets. The bitsets are stored in little-endian order, meaning that the least significant bit
8//! of the first byte is the first bit in the bitset.
9#[cfg(feature = "arrow")]
10mod arrow;
11mod buf;
12mod buf_mut;
13mod macros;
14mod ops;
15
16pub use arrow_buffer::bit_chunk_iterator::BitChunkIterator;
17pub use arrow_buffer::bit_chunk_iterator::BitChunks;
18pub use arrow_buffer::bit_chunk_iterator::UnalignedBitChunk;
19pub use arrow_buffer::bit_chunk_iterator::UnalignedBitChunkIterator;
20pub use arrow_buffer::bit_iterator::BitIndexIterator;
21pub use arrow_buffer::bit_iterator::BitIterator;
22pub use arrow_buffer::bit_iterator::BitSliceIterator;
23pub use buf::*;
24pub use buf_mut::*;
25
26/// Get the bit value at `index` out of `buf`.
27///
28/// # Panics
29///
30/// Panics if `index` is not between 0 and length of `buf * 8`.
31#[inline(always)]
32pub fn get_bit(buf: &[u8], index: usize) -> bool {
33    buf[index / 8] & (1 << (index % 8)) != 0
34}
35
36/// Get the bit value at `index` out of `buf` without bounds checking.
37///
38/// # Safety
39///
40/// `index` must be between 0 and length of `buf * 8`.
41#[inline(always)]
42pub unsafe fn get_bit_unchecked(buf: *const u8, index: usize) -> bool {
43    (unsafe { *buf.add(index / 8) } & (1 << (index % 8))) != 0
44}
45
46/// Set the bit value at `index` in `buf` without bounds checking.
47///
48/// # Safety
49///
50/// `index` must be between 0 and length of `buf * 8`.
51#[inline(always)]
52pub unsafe fn set_bit_unchecked(buf: *mut u8, index: usize) {
53    unsafe { *buf.add(index / 8) |= 1 << (index % 8) };
54}
55
56/// Unset the bit value at `index` in `buf` without bounds checking.
57///
58/// # Safety
59///
60/// `index` must be between 0 and length of `buf * 8`.
61#[inline(always)]
62pub unsafe fn unset_bit_unchecked(buf: *mut u8, index: usize) {
63    unsafe { *buf.add(index / 8) &= !(1 << (index % 8)) };
64}
vortex_buffer/bit/mod.rs

vortex_buffer/bit/
mod.rs
