metatensor/
errors.rs

1use std::ffi::CStr;
2
3use crate::c_api::{mts_status_t, MTS_SUCCESS, MTS_CALLBACK_ERROR};
4
5pub use metatensor_sys::Error;
6
7fn get_last_error(status: Option<mts_status_t>) -> Error {
8    let mut message = std::ptr::null();
9    let mut origin = std::ptr::null();
10    let mut user_data = std::ptr::null_mut();
11    let last_error_status = unsafe {
12        crate::c_api::mts_last_error(
13             &mut message, &mut origin, &mut user_data
14        )
15    };
16
17    if last_error_status != MTS_SUCCESS {
18        return Error {
19            code: status,
20            message: "INTERNAL ERROR: failed to get the last error".into(),
21        };
22    }
23
24    let message = if message.is_null() {
25        "<no message provided>"
26    } else {
27        unsafe { CStr::from_ptr(message).to_str().unwrap_or("<invalid UTF-8 in error message>") }
28    };
29
30    let origin = if origin.is_null() {
31        "<no origin provided>"
32    } else {
33        unsafe { CStr::from_ptr(origin).to_str().unwrap_or("<invalid UTF-8 in error origin>") }
34    };
35
36    if !user_data.is_null() && origin == "Rust Error" {
37        let rust_error = unsafe {
38            user_data.cast::<Error>().as_ref().expect("should not be null")
39        };
40        return rust_error.clone();
41    }
42
43    return Error {
44        code: status,
45        message: message.to_owned(),
46    };
47}
48
49unsafe extern "C" fn error_deleter(data: *mut std::ffi::c_void) {
50    let _ = unsafe { Box::from_raw(data.cast::<Error>()) };
51}
52
53/// Store the last error in the metatensor-core C API, and return
54/// `MTS_CALLBACK_ERROR`
55pub(crate) fn store_last_error(error: Error) -> mts_status_t {
56    let c_message = std::ffi::CString::new(error.message.clone()).expect("found NULL byte in error message");
57    let c_origin = std::ffi::CString::new("Rust Error").expect("found NULL byte in error origin");
58    let status = unsafe {
59        crate::c_api::mts_set_last_error(
60            c_message.as_ptr(),
61            c_origin.as_ptr(),
62            Box::into_raw(Box::new(error)).cast(),
63            Some(error_deleter),
64        )
65    };
66
67    check_status(status).expect("failed to set last error");
68
69    return MTS_CALLBACK_ERROR;
70}
71
72/// Check an `mts_status_t`, returning an error if is it not `MTS_SUCCESS`
73pub fn check_status(status: mts_status_t) -> Result<(), Error> {
74    if status == MTS_SUCCESS {
75        return Ok(())
76    } else {
77        return Err(get_last_error(Some(status)));
78    }
79}
80
81/// Check a pointer allocated by metatensor-core, returning an error if is null
82pub fn check_ptr<T>(ptr: *const T) -> Result<(), Error> {
83    if ptr.is_null() {
84        return Err(get_last_error(None));
85    }
86
87    return Ok(())
88}
89
90
91/// An alternative to `std::panic::catch_unwind` that automatically transform
92/// the error into `mts_status_t`.
93pub(crate) fn catch_unwind<F>(function: F) -> mts_status_t where F: FnOnce() -> Result<(), Error> + std::panic::UnwindSafe {
94    match std::panic::catch_unwind(function) {
95        Ok(Ok(())) => MTS_SUCCESS,
96        Ok(Err(e)) => {
97            return store_last_error(e);
98        },
99        Err(e) => {
100            return store_last_error(e.into());
101        }
102    }
103}
metatensor/errors.rs

metatensor/
errors.rs
