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Diffstat (limited to 'vendor/rustix/src/backend/libc/mod.rs')
-rw-r--r-- | vendor/rustix/src/backend/libc/mod.rs | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/libc/mod.rs b/vendor/rustix/src/backend/libc/mod.rs new file mode 100644 index 0000000..9ecb09f --- /dev/null +++ b/vendor/rustix/src/backend/libc/mod.rs @@ -0,0 +1,215 @@ +//! The libc backend. +//! +//! On most platforms, this uses the `libc` crate to make system calls. On +//! Windows, this uses the Winsock API in `windows-sys`, which can be adapted +//! to have a very `libc`-like interface. + +// Every FFI call requires an unsafe block, and there are a lot of FFI +// calls. For now, set this to allow for the libc backend. +#![allow(clippy::undocumented_unsafe_blocks)] +// Lots of libc types vary between platforms, so we often need a `.into()` on +// one platform where it's redundant on another. +#![allow(clippy::useless_conversion)] + +mod conv; + +#[cfg(windows)] +pub(crate) mod fd { + pub use crate::maybe_polyfill::os::windows::io::{ + AsRawSocket, AsSocket, BorrowedSocket as BorrowedFd, FromRawSocket, IntoRawSocket, + OwnedSocket as OwnedFd, RawSocket as RawFd, + }; + pub(crate) use windows_sys::Win32::Networking::WinSock::SOCKET as LibcFd; + + /// A version of [`AsRawFd`] for use with Winsock API. + /// + /// [`AsRawFd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.AsRawFd.html + pub trait AsRawFd { + /// A version of [`as_raw_fd`] for use with Winsock API. + /// + /// [`as_raw_fd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.FromRawFd.html#tymethod.as_raw_fd + fn as_raw_fd(&self) -> RawFd; + } + impl<T: AsRawSocket> AsRawFd for T { + #[inline] + fn as_raw_fd(&self) -> RawFd { + self.as_raw_socket() + } + } + + /// A version of [`IntoRawFd`] for use with Winsock API. + /// + /// [`IntoRawFd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.IntoRawFd.html + pub trait IntoRawFd { + /// A version of [`into_raw_fd`] for use with Winsock API. + /// + /// [`into_raw_fd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.FromRawFd.html#tymethod.into_raw_fd + fn into_raw_fd(self) -> RawFd; + } + impl<T: IntoRawSocket> IntoRawFd for T { + #[inline] + fn into_raw_fd(self) -> RawFd { + self.into_raw_socket() + } + } + + /// A version of [`FromRawFd`] for use with Winsock API. + /// + /// [`FromRawFd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.FromRawFd.html + pub trait FromRawFd { + /// A version of [`from_raw_fd`] for use with Winsock API. + /// + /// # Safety + /// + /// See the [safety requirements] for [`from_raw_fd`]. + /// + /// [`from_raw_fd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.FromRawFd.html#tymethod.from_raw_fd + /// [safety requirements]: https://doc.rust-lang.org/stable/std/os/fd/trait.FromRawFd.html#safety + unsafe fn from_raw_fd(raw_fd: RawFd) -> Self; + } + impl<T: FromRawSocket> FromRawFd for T { + #[inline] + unsafe fn from_raw_fd(raw_fd: RawFd) -> Self { + Self::from_raw_socket(raw_fd) + } + } + + /// A version of [`AsFd`] for use with Winsock API. + /// + /// [`AsFd`]: https://doc.rust-lang.org/stable/std/os/fd/trait.AsFd.html + pub trait AsFd { + /// An `as_fd` function for Winsock, where a `Fd` is a `Socket`. + fn as_fd(&self) -> BorrowedFd; + } + impl<T: AsSocket> AsFd for T { + #[inline] + fn as_fd(&self) -> BorrowedFd { + self.as_socket() + } + } +} +#[cfg(not(windows))] +pub(crate) mod fd { + pub use crate::maybe_polyfill::os::fd::{ + AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, OwnedFd, RawFd, + }; + #[allow(unused_imports)] + pub(crate) use RawFd as LibcFd; +} + +// On Windows we emulate selected libc-compatible interfaces. On non-Windows, +// we just use libc here, since this is the libc backend. +#[cfg_attr(windows, path = "winsock_c.rs")] +pub(crate) mod c; + +#[cfg(feature = "event")] +pub(crate) mod event; +#[cfg(not(windows))] +#[cfg(feature = "fs")] +pub(crate) mod fs; +pub(crate) mod io; +#[cfg(linux_kernel)] +#[cfg(feature = "io_uring")] +pub(crate) mod io_uring; +#[cfg(not(any(windows, target_os = "espidf", target_os = "vita", target_os = "wasi")))] +#[cfg(feature = "mm")] +pub(crate) mod mm; +#[cfg(linux_kernel)] +#[cfg(feature = "mount")] +pub(crate) mod mount; +#[cfg(linux_kernel)] +#[cfg(all(feature = "fs", not(feature = "mount")))] +pub(crate) mod mount; // for deprecated mount functions in "fs" +#[cfg(not(any(target_os = "redox", target_os = "wasi")))] +#[cfg(feature = "net")] +pub(crate) mod net; +#[cfg(not(any(windows, target_os = "espidf")))] +#[cfg(any( + feature = "param", + feature = "runtime", + feature = "time", + target_arch = "x86", +))] +pub(crate) mod param; +#[cfg(not(windows))] +#[cfg(feature = "pipe")] +pub(crate) mod pipe; +#[cfg(not(windows))] +#[cfg(feature = "process")] +pub(crate) mod process; +#[cfg(not(windows))] +#[cfg(not(target_os = "wasi"))] +#[cfg(feature = "pty")] +pub(crate) mod pty; +#[cfg(not(windows))] +#[cfg(feature = "rand")] +pub(crate) mod rand; +#[cfg(not(windows))] +#[cfg(not(target_os = "wasi"))] +#[cfg(feature = "system")] +pub(crate) mod system; +#[cfg(not(any(windows, target_os = "vita")))] +#[cfg(feature = "termios")] +pub(crate) mod termios; +#[cfg(not(windows))] +#[cfg(feature = "thread")] +pub(crate) mod thread; +#[cfg(not(any(windows, target_os = "espidf")))] +#[cfg(feature = "time")] +pub(crate) mod time; + +/// If the host libc is glibc, return `true` if it is less than version 2.25. +/// +/// To restate and clarify, this function returning true does not mean the libc +/// is glibc just that if it is glibc, it is less than version 2.25. +/// +/// For now, this function is only available on Linux, but if it ends up being +/// used beyond that, this could be changed to e.g. `#[cfg(unix)]`. +#[cfg(all(unix, target_env = "gnu"))] +pub(crate) fn if_glibc_is_less_than_2_25() -> bool { + // This is also defined inside `weak_or_syscall!` in + // backend/libc/rand/syscalls.rs, but it's not convenient to re-export the + // weak symbol from that macro, so we duplicate it at a small cost here. + weak! { fn getrandom(*mut c::c_void, c::size_t, c::c_uint) -> c::ssize_t } + + // glibc 2.25 has `getrandom`, which is how we satisfy the API contract of + // this function. But, there are likely other libc versions which have it. + getrandom.get().is_none() +} + +// Private modules used by multiple public modules. +#[cfg(any(feature = "procfs", feature = "process", feature = "runtime"))] +#[cfg(not(any(windows, target_os = "wasi")))] +pub(crate) mod pid; +#[cfg(any(feature = "process", feature = "thread"))] +#[cfg(linux_kernel)] +pub(crate) mod prctl; +#[cfg(not(any( + windows, + target_os = "android", + target_os = "espidf", + target_os = "vita", + target_os = "wasi" +)))] +#[cfg(feature = "shm")] +pub(crate) mod shm; +#[cfg(any(feature = "fs", feature = "thread", feature = "process"))] +#[cfg(not(any(windows, target_os = "wasi")))] +pub(crate) mod ugid; + +#[cfg(bsd)] +const MAX_IOV: usize = c::IOV_MAX as usize; + +#[cfg(any(linux_kernel, target_os = "emscripten", target_os = "nto"))] +const MAX_IOV: usize = c::UIO_MAXIOV as usize; + +#[cfg(not(any( + bsd, + linux_kernel, + windows, + target_os = "emscripten", + target_os = "espidf", + target_os = "nto", + target_os = "horizon", +)))] +const MAX_IOV: usize = 16; // The minimum value required by POSIX. |