1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
//!Implementation of [xxHash](https://github.com/Cyan4973/xxHash) in Rust
//!
//!Version corresponds to xxHash [releases](https://github.com/Cyan4973/xxHash/releases)
//!
//!Each algorithm is implemented via feature, allowing precise control over code size.
//!
//!## Example
//!
//!- Cargo.toml
//!
//!```toml
//![dependencies.xxhash-rust]
//!version = "0.8.5"
//!features = ["xxh3", "const_xxh3"]
//!```
//!
//!- main.rs
//!
//!```rust
//!use xxhash_rust::const_xxh3::xxh3_64 as const_xxh3;
//!use xxhash_rust::xxh3::xxh3_64;
//!
//!const TEST: u64 = const_xxh3(b"TEST");
//!
//!fn test_input(text: &str) -> bool {
//!    match xxh3_64(text.as_bytes()) {
//!        TEST => true,
//!        _ => false
//!    }
//!}
//!
//!assert!(!test_input("tEST"));
//!assert!(test_input("TEST"));
//!```
//!
//!## Features:
//!
//!By default all features are off.
//!
//!- `std` - Enables `std::io::Write` trait implementation
//!- `xxh32` - Enables 32bit algorithm. Suitable for x86 targets
//!- `const_xxh32` - `const fn` version of `xxh32` algorithm
//!- `xxh64` - Enables 64 algorithm. Suitable for x86_64 targets
//!- `const_xxh64` - `const fn` version of `xxh64` algorithm
//!- `xxh3` - Enables `xxh3` family of algorithms, superior to `xxh32` and `xxh64` in terms of performance.
//!- `const_xxh3` - `const fn` version of `xxh3` algorithm
//!
//!## HW acceleration
//!
//!Similar to reference implementation, crate implements various SIMDs in `xxh3` depending on provided flags.
//!All checks are performed only at compile time, hence user is encouraged to enable these accelerations (for example via `-C target_cpu=native`)
//!
//!Used SIMD acceleration:
//!
//!- SSE2 - widely available, can be safely enabled in 99% of cases. Enabled by default in `x86_64` targets.
//!- AVX2;
//!- Neon - Enabled by default on aarch64 targets (most likely);
//!- Wasm SIMD128 - Has to be enabled via rust flag: `-Ctarget-feature=+simd128`
//!
//!## Streaming vs One-shot
//!
//!For performance reasons one-shot version of algorithm does not re-use streaming version.
//!Unless needed, user is advised to use one-shot version which tends to be more optimal.
//!
//!## `cosnt fn` version
//!
//!While `const fn` provides compile time implementation, it does so at performance cost.
//!Hence you should only use it at _compile_ time.
//!
//!To guarantee that something is computed at compile time make sure to initialize hash output
//!as `const` or `static` variable, otherwise it is possible function is executed at runtime, which
//!would be worse than regular algorithm.
//!
//!`const fn` is implemented in best possible way while conforming to limitations of Rust `const
//!fn`, but these limitations are quite strict making any high performance code impossible.

#![no_std]
#![warn(missing_docs)]
#![cfg_attr(feature = "cargo-clippy", allow(clippy::style))]

#[cfg(feature = "std")]
extern crate std;

#[cfg(any(feature = "xxh32", feature = "const_xxh32", feature = "xxh3", feature = "const_xxh3"))]
mod xxh32_common;
#[cfg(feature = "xxh32")]
pub mod xxh32;
#[cfg(feature = "const_xxh32")]
pub mod const_xxh32;

#[cfg(any(feature = "xxh64", feature = "const_xxh64", feature = "xxh3", feature = "const_xxh3"))]
mod xxh64_common;
#[cfg(feature = "xxh64")]
pub mod xxh64;
#[cfg(feature = "const_xxh64")]
pub mod const_xxh64;

#[cfg(any(feature = "xxh3", feature = "const_xxh3"))]
mod xxh3_common;
#[cfg(feature = "xxh3")]
pub mod xxh3;
#[cfg(feature = "const_xxh3")]
pub mod const_xxh3;