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
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
//! The following is derived from Rust's
//! library/std/src/os/fd/raw.rs at revision
//! fa68e73e9947be8ffc5b3b46d899e4953a44e7e9.
//!
//! Raw Unix-like file descriptors.
#![cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
#![allow(unsafe_code)]
use crate::backend::c;
/// Raw file descriptors.
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
pub type RawFd = c::c_int;
/// A trait to extract the raw file descriptor from an underlying object.
///
/// This is only available on unix and WASI platforms and must be imported in
/// order to call the method. Windows platforms have a corresponding
/// `AsRawHandle` and `AsRawSocket` set of traits.
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
pub trait AsRawFd {
/// Extracts the raw file descriptor.
///
/// This function is typically used to **borrow** an owned file descriptor.
/// When used in this way, this method does **not** pass ownership of the
/// raw file descriptor to the caller, and the file descriptor is only
/// guaranteed to be valid while the original object has not yet been
/// destroyed.
///
/// However, borrowing is not strictly required. See [`AsFd::as_fd`]
/// for an API which strictly borrows a file descriptor.
///
/// # Example
///
/// ```no_run
/// use std::fs::File;
/// # use std::io;
/// #[cfg(unix)]
/// use std::os::unix::io::{AsRawFd, RawFd};
/// #[cfg(target_os = "wasi")]
/// use std::os::wasi::io::{AsRawFd, RawFd};
///
/// let mut f = File::open("foo.txt")?;
/// // `raw_fd` is only valid as long as `f` exists.
/// #[cfg(any(unix, target_os = "wasi"))]
/// let raw_fd: RawFd = f.as_raw_fd();
/// # Ok::<(), io::Error>(())
/// ```
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
fn as_raw_fd(&self) -> RawFd;
}
/// A trait to express the ability to construct an object from a raw file
/// descriptor.
#[cfg_attr(staged_api, stable(feature = "from_raw_os", since = "1.1.0"))]
pub trait FromRawFd {
/// Constructs a new instance of `Self` from the given raw file
/// descriptor.
///
/// This function is typically used to **consume ownership** of the
/// specified file descriptor. When used in this way, the returned object
/// will take responsibility for closing it when the object goes out of
/// scope.
///
/// However, consuming ownership is not strictly required. Use a
/// [`From<OwnedFd>::from`] implementation for an API which strictly
/// consumes ownership.
///
/// # Safety
///
/// The `fd` passed in must be a valid an open file descriptor.
///
/// # Example
///
/// ```no_run
/// use std::fs::File;
/// # use std::io;
/// #[cfg(unix)]
/// use std::os::unix::io::{FromRawFd, IntoRawFd, RawFd};
/// #[cfg(target_os = "wasi")]
/// use std::os::wasi::io::{FromRawFd, IntoRawFd, RawFd};
///
/// let f = File::open("foo.txt")?;
/// # #[cfg(any(unix, target_os = "wasi"))]
/// let raw_fd: RawFd = f.into_raw_fd();
/// // SAFETY: no other functions should call `from_raw_fd`, so there
/// // is only one owner for the file descriptor.
/// # #[cfg(any(unix, target_os = "wasi"))]
/// let f = unsafe { File::from_raw_fd(raw_fd) };
/// # Ok::<(), io::Error>(())
/// ```
#[cfg_attr(staged_api, stable(feature = "from_raw_os", since = "1.1.0"))]
unsafe fn from_raw_fd(fd: RawFd) -> Self;
}
/// A trait to express the ability to consume an object and acquire ownership of
/// its raw file descriptor.
#[cfg_attr(staged_api, stable(feature = "into_raw_os", since = "1.4.0"))]
pub trait IntoRawFd {
/// Consumes this object, returning the raw underlying file descriptor.
///
/// This function is typically used to **transfer ownership** of the underlying
/// file descriptor to the caller. When used in this way, callers are then the unique
/// owners of the file descriptor and must close it once it's no longer needed.
///
/// However, transferring ownership is not strictly required. Use a
/// [`Into<OwnedFd>::into`] implementation for an API which strictly
/// transfers ownership.
///
/// # Example
///
/// ```no_run
/// use std::fs::File;
/// # use std::io;
/// #[cfg(unix)]
/// use std::os::unix::io::{IntoRawFd, RawFd};
/// #[cfg(target_os = "wasi")]
/// use std::os::wasi::io::{IntoRawFd, RawFd};
///
/// let f = File::open("foo.txt")?;
/// #[cfg(any(unix, target_os = "wasi"))]
/// let raw_fd: RawFd = f.into_raw_fd();
/// # Ok::<(), io::Error>(())
/// ```
#[cfg_attr(staged_api, stable(feature = "into_raw_os", since = "1.4.0"))]
fn into_raw_fd(self) -> RawFd;
}
#[cfg_attr(
staged_api,
stable(feature = "raw_fd_reflexive_traits", since = "1.48.0")
)]
impl AsRawFd for RawFd {
#[inline]
fn as_raw_fd(&self) -> RawFd {
*self
}
}
#[cfg_attr(
staged_api,
stable(feature = "raw_fd_reflexive_traits", since = "1.48.0")
)]
impl IntoRawFd for RawFd {
#[inline]
fn into_raw_fd(self) -> RawFd {
self
}
}
#[cfg_attr(
staged_api,
stable(feature = "raw_fd_reflexive_traits", since = "1.48.0")
)]
impl FromRawFd for RawFd {
#[inline]
unsafe fn from_raw_fd(fd: RawFd) -> RawFd {
fd
}
}
|
