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 count_ones;
14mod macros;
15mod ops;
16
17pub use arrow_buffer::bit_chunk_iterator::BitChunkIterator;
18pub use arrow_buffer::bit_chunk_iterator::BitChunks;
19pub use arrow_buffer::bit_chunk_iterator::UnalignedBitChunk;
20pub use arrow_buffer::bit_chunk_iterator::UnalignedBitChunkIterator;
21pub use arrow_buffer::bit_iterator::BitIndexIterator;
22pub use arrow_buffer::bit_iterator::BitIterator;
23pub use arrow_buffer::bit_iterator::BitSliceIterator;
24pub use buf::*;
25pub use buf_mut::*;
26
27/// Get the bit value at `index` out of `buf`.
28///
29/// # Panics
30///
31/// Panics if `index` is not between 0 and length of `buf * 8`.
32#[inline(always)]
33pub fn get_bit(buf: &[u8], index: usize) -> bool {
34    buf[index / 8] & (1 << (index % 8)) != 0
35}
36
37/// Get the bit value at `index` out of `buf` without bounds checking.
38///
39/// # Safety
40///
41/// `index` must be between 0 and length of `buf * 8`.
42#[inline(always)]
43pub unsafe fn get_bit_unchecked(buf: *const u8, index: usize) -> bool {
44    (unsafe { *buf.add(index / 8) } & (1 << (index % 8))) != 0
45}
46
47/// Set the bit value at `index` in `buf` without bounds checking.
48///
49/// # Safety
50///
51/// `index` must be between 0 and length of `buf * 8`.
52#[inline(always)]
53pub unsafe fn set_bit_unchecked(buf: *mut u8, index: usize) {
54    unsafe { *buf.add(index / 8) |= 1 << (index % 8) };
55}
56
57/// Unset the bit value at `index` in `buf` without bounds checking.
58///
59/// # Safety
60///
61/// `index` must be between 0 and length of `buf * 8`.
62#[inline(always)]
63pub unsafe fn unset_bit_unchecked(buf: *mut u8, index: usize) {
64    unsafe { *buf.add(index / 8) &= !(1 << (index % 8)) };
65}
vortex_buffer/bit/mod.rs

vortex_buffer/bit/
mod.rs
