1//! The Unix `ioctl` function is effectively lots of different functions hidden
2//! behind a single dynamic dispatch interface. In order to provide a type-safe
3//! API, rustix makes them all separate functions so that they can have
4//! dedicated static type signatures.
5//!
6//! Some ioctls, such as those related to filesystems, terminals, and
7//! processes, live in other top-level API modules.
8
9#![allow(unsafe_code)]
10
11use crate::{backend, io, ioctl};
12use backend::c;
13use backend::fd::AsFd;
14
15/// `ioctl(fd, FIOCLEX, NULL)`—Set the close-on-exec flag.
16///
17/// This is similar to `fcntl(fd, F_SETFD, FD_CLOEXEC)`, except that it avoids
18/// clearing any other flags that might be set.
19#[cfg(apple)]
20#[inline]
21#[doc(alias = "FIOCLEX")]
22#[doc(alias = "FD_CLOEXEC")]
23pub fn ioctl_fioclex<Fd: AsFd>(fd: Fd) -> io::Result<()> {
24 // SAFETY: `FIOCLEX` is a no-argument setter opcode.
25 unsafe {
26 let ctl = ioctl::NoArg::<ioctl::BadOpcode<{ c::FIOCLEX }>>::new();
27 ioctl::ioctl(fd, ctl)
28 }
29}
30
31/// `ioctl(fd, FIONBIO, &value)`—Enables or disables non-blocking mode.
32///
33/// # References
34/// - [Winsock]
35/// - [NetBSD]
36/// - [OpenBSD]
37///
38/// [Winsock]: https://docs.microsoft.com/en-us/windows/win32/winsock/winsock-ioctls#unix-ioctl-codes
39/// [NetBSD]: https://man.netbsd.org/ioctl.2#GENERIC%20IOCTLS
40/// [OpenBSD]: https://man.openbsd.org/ioctl.2#GENERIC_IOCTLS
41#[inline]
42#[doc(alias = "FIONBIO")]
43pub fn ioctl_fionbio<Fd: AsFd>(fd: Fd, value: bool) -> io::Result<()> {
44 // SAFETY: `FIONBIO` is a pointer setter opcode.
45 unsafe {
46 let ctl: Setter, i32> = ioctl::Setter::<ioctl::BadOpcode<{ c::FIONBIO }>, c::c_int>::new(input:value.into());
47 ioctl::ioctl(fd, ioctl:ctl)
48 }
49}
50
51/// `ioctl(fd, FIONREAD)`—Returns the number of bytes ready to be read.
52///
53/// The result of this function gets silently coerced into a C `int` by the OS,
54/// so it may contain a wrapped value.
55///
56/// # References
57/// - [Linux]
58/// - [Winsock]
59/// - [FreeBSD]
60/// - [NetBSD]
61/// - [OpenBSD]
62///
63/// [Linux]: https://man7.org/linux/man-pages/man2/ioctl_tty.2.html
64/// [Winsock]: https://docs.microsoft.com/en-us/windows/win32/winsock/winsock-ioctls#unix-ioctl-codes
65/// [FreeBSD]: https://man.freebsd.org/cgi/man.cgi?query=ioctl&sektion=2#GENERIC%09IOCTLS
66/// [NetBSD]: https://man.netbsd.org/ioctl.2#GENERIC%20IOCTLS
67/// [OpenBSD]: https://man.openbsd.org/ioctl.2#GENERIC_IOCTLS
68#[cfg(not(any(target_os = "espidf", target_os = "horizon", target_os = "vita")))]
69#[inline]
70#[doc(alias = "FIONREAD")]
71pub fn ioctl_fionread<Fd: AsFd>(fd: Fd) -> io::Result<u64> {
72 // SAFETY: `FIONREAD` is a getter opcode that gets a `c_int`.
73 unsafe {
74 let ctl: Getter, i32> = ioctl::Getter::<ioctl::BadOpcode<{ c::FIONREAD }>, c::c_int>::new();
75 ioctl::ioctl(fd, ctl).map(|n: i32| n as u64)
76 }
77}
78