diff --git a/src/net/if_.rs b/src/net/if_.rs index 70349e5cfd..343b3e092e 100644 --- a/src/net/if_.rs +++ b/src/net/if_.rs @@ -3,8 +3,8 @@ //! Uses Linux and/or POSIX functions to resolve interface names like "eth0" //! or "socan1" into device numbers. +use crate::{Error, NixPath, Result}; use libc::c_uint; -use crate::{Result, Error, NixPath}; /// Resolve an interface into a interface number. pub fn if_nametoindex(name: &P) -> Result { @@ -267,3 +267,147 @@ libc_bitflags!( IFF_IPMP; } ); + +#[cfg(any( + target_os = "dragonfly", + target_os = "freebsd", + target_os = "fuchsia", + target_os = "ios", + target_os = "linux", + target_os = "macos", + target_os = "netbsd", + target_os = "openbsd", +))] +mod get_interfaces { + use super::*; + + use std::ffi::CStr; + use std::fmt; + use std::marker::PhantomData; + use std::ptr::NonNull; + + /// A network interface. Has a name like "eth0" or "wlp4s0" or "wlan0", as well as an index + /// (1, 2, 3, etc) that identifies it in the OS's networking stack. + #[allow(missing_copy_implementations)] + #[repr(transparent)] + pub struct Interface(libc::if_nameindex); + + impl Interface { + /// Obtain the index of this interface. + pub fn index(&self) -> c_uint { + self.0.if_index + } + + /// Obtain the name of this interface. + pub fn name(&self) -> &CStr { + unsafe { CStr::from_ptr(self.0.if_name) } + } + } + + impl fmt::Debug for Interface { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + f.debug_struct("Interface") + .field("index", &self.index()) + .field("name", &self.name()) + .finish() + } + } + + /// A list of the network interfaces available on this system. Obtained from [`interfaces()`]. + pub struct Interfaces { + ptr: NonNull, + } + + impl Interfaces { + /// Iterate over the interfaces in this list. + #[inline] + pub fn iter(&self) -> InterfacesIter<'_> { + self.into_iter() + } + + /// Convert this to a slice of interfaces. Note that the underlying interfaces list is + /// null-terminated, so calling this calculates the length. If random access isn't needed, + /// [`Interfaces::iter()`] should be used instead. + pub fn to_slice(&self) -> &[Interface] { + let ifs = self.ptr.as_ptr() as *const Interface; + let len = self.iter().count(); + unsafe { std::slice::from_raw_parts(ifs, len) } + } + } + + impl Drop for Interfaces { + fn drop(&mut self) { + unsafe { libc::if_freenameindex(self.ptr.as_ptr()) }; + } + } + + impl fmt::Debug for Interfaces { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + self.to_slice().fmt(f) + } + } + + impl<'a> IntoIterator for &'a Interfaces { + type IntoIter = InterfacesIter<'a>; + type Item = &'a Interface; + #[inline] + fn into_iter(self) -> Self::IntoIter { + InterfacesIter { + ptr: self.ptr.as_ptr(), + _marker: PhantomData, + } + } + } + + /// An iterator over the interfaces in an [`Interfaces`]. + #[derive(Debug)] + pub struct InterfacesIter<'a> { + ptr: *const libc::if_nameindex, + _marker: PhantomData<&'a Interfaces>, + } + + impl<'a> Iterator for InterfacesIter<'a> { + type Item = &'a Interface; + #[inline] + fn next(&mut self) -> Option { + unsafe { + if (*self.ptr).if_index == 0 { + None + } else { + let ret = &*(self.ptr as *const Interface); + self.ptr = self.ptr.add(1); + Some(ret) + } + } + } + } + + /// Retrieve information about the network interfaces available on the local system. + /// + /// ```no_run + /// # fn main() -> nix::Result<()> { + /// let interfaces = nix::net::if_::interfaces()?; + /// for iface in &interfaces { + /// println!("Interface #{} is called {}", iface.index(), iface.name().to_string_lossy()); + /// } + /// # Ok(()) } + /// ``` + pub fn interfaces() -> Result { + unsafe { + let ifs = libc::if_nameindex(); + let ptr = NonNull::new(ifs).ok_or_else(Error::last)?; + Ok(Interfaces { ptr }) + } + } +} +#[cfg(any( + target_os = "dragonfly", + target_os = "freebsd", + target_os = "fuchsia", + target_os = "ios", + target_os = "linux", + target_os = "macos", + target_os = "netbsd", + target_os = "openbsd", +))] +pub use get_interfaces::*;