wasmtime-wasi 18.0.3

WASI implementation in Rust
Documentation 
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

//! `wasmtime-wasi` now supports using multiple snapshots to interface to the
//! same `WasiCtx`!
//!
//! `wasmtime_wasi::Wasi::new(&Store, WasiCtx)` is a struct which owns your
//! `WasiCtx` and provides linkage to every available snapshot.
//!
//! Individual snapshots are available through
//! `wasmtime_wasi::snapshots::preview_{0, 1}::Wasi::new(&Store, Rc<RefCell<WasiCtx>>)`.

#![warn(clippy::cast_sign_loss)]

#[cfg(feature = "preview2")]
pub mod preview2;

#[cfg(feature = "wasi-common-deprecations")]
#[deprecated(
    since = "18.0.0",
    note = "The wasmtime_wasi::sync module's functionalty has been moved to
    wasi_common::sync. This re-export will be removed from wasmtime_wasi in
    19.0"
)]
pub mod sync {
    pub use wasi_common::sync::*;
}

#[cfg(feature = "wasi-common-deprecations")]
#[allow(deprecated)] // Satisfy linter locally
#[deprecated(
    since = "18.0.0",
    note = "The wasmtime_wasi module's root export of wasmtime_wasi::sync has
    been moved to wasi_common::sync. This re-export will be removed from
    wasmtime_wasi in 19.0"
)]
pub use sync::*;

#[cfg(feature = "tokio")]
#[deprecated(
    since = "18.0.0",
    note = "The wasmtime_wasi::tokio module's functionalty has been moved to
    wasi_common::tokio. This re-export will be removed from wasmtime_wasi in
    19.0"
)]
pub mod tokio {
    pub use wasi_common::tokio::*;
}

/// Exit the process with a conventional OS error code as long as Wasmtime
/// understands the error. If the error is not an `I32Exit` or `Trap`, return
/// the error back to the caller for it to decide what to do.
///
/// Note: this function is designed for usage where it is acceptable for
/// Wasmtime failures to terminate the parent process, such as in the Wasmtime
/// CLI; this would not be suitable for use in multi-tenant embeddings.
#[cfg(feature = "exit")]
#[deprecated(
    since = "18.0.0",
    note = "This legacy functionality is migrated to the wasi-common crate, and will be removed in 19.0."
)]
pub fn maybe_exit_on_error(e: anyhow::Error) -> anyhow::Error {
    use std::process;
    use wasmtime::Trap;

    if let Some(exit) = e
        .downcast_ref::<preview2::I32Exit>()
        .map(|exit| exit.process_exit_code())
    {
        process::exit(exit)
    }

    // If a specific WASI error code was requested then that's
    // forwarded through to the process here without printing any
    // extra error information.
    let code = e.downcast_ref::<wasi_common::I32Exit>().map(|e| e.0);
    if let Some(exit) = code {
        // Print the error message in the usual way.
        // On Windows, exit status 3 indicates an abort (see below),
        // so return 1 indicating a non-zero status to avoid ambiguity.
        if cfg!(windows) && exit >= 3 {
            process::exit(1);
        }
        process::exit(exit);
    }

    // If the program exited because of a trap, return an error code
    // to the outside environment indicating a more severe problem
    // than a simple failure.
    if e.is::<Trap>() {
        eprintln!("Error: {:?}", e);

        cfg_if::cfg_if! {
            if #[cfg(unix)] {
                // On Unix, return the error code of an abort.
                process::exit(rustix::process::EXIT_SIGNALED_SIGABRT);
            } else if #[cfg(windows)] {
                // On Windows, return 3.
                // https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/abort?view=vs-2019
                process::exit(3);
            }
        }
    }

    e
}