nautilus_core/ffi/
uuid.rs

1// -------------------------------------------------------------------------------------------------
2//  Copyright (C) 2015-2026 Nautech Systems Pty Ltd. All rights reserved.
3//  https://nautechsystems.io
4//
5//  Licensed under the GNU Lesser General Public License Version 3.0 (the "License");
6//  You may not use this file except in compliance with the License.
7//  You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-3.0.en.html
8//
9//  Unless required by applicable law or agreed to in writing, software
10//  distributed under the License is distributed on an "AS IS" BASIS,
11//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12//  See the License for the specific language governing permissions and
13//  limitations under the License.
14// -------------------------------------------------------------------------------------------------
15
16//! FFI helpers for the [`UUID4`] wrapper type.
17//!
18//! The functions exported here make it possible for C/Python code to create, compare, and hash
19//! UUID values *without* having to understand the internal representation chosen by
20//! NautilusTrader.
21
22use std::{
23    collections::hash_map::DefaultHasher,
24    ffi::{CStr, c_char},
25    hash::{Hash, Hasher},
26};
27
28use crate::{UUID4, ffi::abort_on_panic};
29
30/// Generate a new random (version-4) UUID and return it by value.
31#[unsafe(no_mangle)]
32pub extern "C" fn uuid4_new() -> UUID4 {
33    abort_on_panic(UUID4::new)
34}
35
36/// Returns a [`UUID4`] from C string pointer.
37///
38/// # Safety
39///
40/// Assumes `ptr` is a valid C string pointer.
41///
42/// # Panics
43///
44/// Panics if `ptr` cannot be cast to a valid C string.
45#[unsafe(no_mangle)]
46pub unsafe extern "C" fn uuid4_from_cstr(ptr: *const c_char) -> UUID4 {
47    abort_on_panic(|| {
48        assert!(!ptr.is_null(), "`ptr` was NULL");
49        // SAFETY: Caller guarantees ptr is valid per function contract
50        let cstr = unsafe { CStr::from_ptr(ptr) };
51        let value = cstr.to_str().expect("Failed to convert C string to UTF-8");
52        UUID4::from(value)
53    })
54}
55
56/// Return a borrowed *null-terminated* UTF-8 C string representing `uuid`.
57///
58/// The pointer remains valid for as long as the input `UUID4` reference lives – callers **must
59/// not** attempt to free it.
60#[unsafe(no_mangle)]
61pub extern "C" fn uuid4_to_cstr(uuid: &UUID4) -> *const c_char {
62    abort_on_panic(|| uuid.to_cstr().as_ptr())
63}
64
65/// Compare two UUID values, returning `1` when they are equal and `0` otherwise.
66#[unsafe(no_mangle)]
67pub extern "C" fn uuid4_eq(lhs: &UUID4, rhs: &UUID4) -> u8 {
68    abort_on_panic(|| u8::from(lhs == rhs))
69}
70
71/// Compute the stable [`u64`] hash of `uuid` using Rust’s default hasher.
72#[unsafe(no_mangle)]
73pub extern "C" fn uuid4_hash(uuid: &UUID4) -> u64 {
74    abort_on_panic(|| {
75        let mut h = DefaultHasher::new();
76        uuid.hash(&mut h);
77        h.finish()
78    })
79}
80
81#[cfg(test)]
82mod tests {
83    use std::ffi::CString;
84
85    use rstest::*;
86    use uuid::{self, Uuid};
87
88    use super::*;
89
90    #[rstest]
91    fn test_new() {
92        let uuid = uuid4_new();
93        let uuid_string = uuid.to_string();
94        let uuid_parsed = Uuid::parse_str(&uuid_string).expect("Uuid::parse_str failed");
95        assert_eq!(uuid_parsed.get_version().unwrap(), uuid::Version::Random);
96    }
97
98    #[rstest]
99    fn test_from_cstr() {
100        let uuid_string = "2d89666b-1a1e-4a75-b193-4eb3b454c757";
101        let uuid_cstring = CString::new(uuid_string).expect("CString::new failed");
102        let uuid_ptr = uuid_cstring.as_ptr();
103        let uuid = unsafe { uuid4_from_cstr(uuid_ptr) };
104        assert_eq!(uuid_string, uuid.to_string());
105    }
106
107    #[rstest]
108    fn test_to_cstr() {
109        let uuid_string = "2d89666b-1a1e-4a75-b193-4eb3b454c757";
110        let uuid = UUID4::from(uuid_string);
111        let uuid_ptr = uuid4_to_cstr(&uuid);
112        let uuid_cstr = unsafe { CStr::from_ptr(uuid_ptr) };
113        let uuid_result_string = uuid_cstr.to_str().expect("CStr::to_str failed").to_string();
114        assert_eq!(uuid_string, uuid_result_string);
115    }
116
117    #[rstest]
118    fn test_eq() {
119        let uuid1 = UUID4::from("2d89666b-1a1e-4a75-b193-4eb3b454c757");
120        let uuid2 = UUID4::from("2d89666b-1a1e-4a75-b193-4eb3b454c757");
121        let uuid3 = UUID4::from("2d89666b-1a1e-4a75-b193-4eb3b454c758");
122        assert_eq!(uuid4_eq(&uuid1, &uuid2), 1);
123        assert_eq!(uuid4_eq(&uuid1, &uuid3), 0);
124    }
125
126    #[rstest]
127    fn test_hash() {
128        let uuid1 = UUID4::from("2d89666b-1a1e-4a75-b193-4eb3b454c757");
129        let uuid2 = UUID4::from("2d89666b-1a1e-4a75-b193-4eb3b454c757");
130        let uuid3 = UUID4::from("2d89666b-1a1e-4a75-b193-4eb3b454c758");
131        assert_eq!(uuid4_hash(&uuid1), uuid4_hash(&uuid2));
132        assert_ne!(uuid4_hash(&uuid1), uuid4_hash(&uuid3));
133    }
134}
nautilus_core/ffi/uuid.rs

nautilus_core/ffi/
uuid.rs
