changes from feedback

Author: devnexen

library/std/src/os/unix/net/datagram.rs

@@ -16,7 +16,7 @@ use libc::MSG_NOSIGNAL;
 use super::{recv_vectored_with_ancillary_from, send_vectored_with_ancillary_to, SocketAncillary};
 use super::{sockaddr_un, SocketAddr};
 #[cfg(any(doc, target_os = "linux", target_os = "haiku", target_os = "vxworks",))]
-use crate::ffi::CStr;
+use crate::ffi::{CStr, CString};
 #[cfg(any(doc, target_os = "android", target_os = "linux"))]
 use crate::io::{IoSlice, IoSliceMut};
 use crate::net::Shutdown;
@@ -886,7 +886,7 @@ impl UnixDatagram {
     /// ```
     #[cfg(any(doc, target_os = "linux", target_os = "haiku", target_os = "vxworks",))]
     #[unstable(feature = "unix_set_todevice", issue = "129182")]
-    pub fn todevice(&self) -> io::Result<&CStr> {
+    pub fn todevice(&self) -> io::Result<CString> {
         self.0.todevice()
     }
     /// Returns the value of the `SO_ERROR` option.

library/std/src/os/unix/net/stream.rs

@@ -13,7 +13,7 @@ use super::{peer_cred, UCred};
 use super::{recv_vectored_with_ancillary_from, send_vectored_with_ancillary_to, SocketAncillary};
 use super::{sockaddr_un, SocketAddr};
 #[cfg(any(doc, target_os = "linux", target_os = "haiku", target_os = "vxworks",))]
-use crate::ffi::CStr;
+use crate::ffi::{CStr, CString};
 use crate::fmt;
 use crate::io::{self, IoSlice, IoSliceMut};
 use crate::net::Shutdown;
@@ -455,7 +455,7 @@ impl UnixStream {
     /// ```
     #[cfg(any(doc, target_os = "linux", target_os = "haiku", target_os = "vxworks",))]
     #[unstable(feature = "unix_set_todevice", issue = "129182")]
-    pub fn todevice(&self) -> io::Result<&CStr> {
+    pub fn todevice(&self) -> io::Result<CString> {
         self.0.todevice()
     }
 

library/std/src/sys/pal/unix/net.rs

@@ -1,6 +1,6 @@
 use libc::{c_int, c_void, size_t, sockaddr, socklen_t, MSG_PEEK};
 
-use crate::ffi::CStr;
+use crate::ffi::{CStr, CString};
 use crate::io::{self, BorrowedBuf, BorrowedCursor, IoSlice, IoSliceMut};
 use crate::net::{Shutdown, SocketAddr};
 use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, RawFd};
@@ -564,18 +564,24 @@ impl Socket {
     }
 
     #[cfg(any(target_os = "linux", target_os = "haiku", target_os = "vxworks"))]
-    pub fn todevice(&self) -> io::Result<&CStr> {
+    pub fn todevice(&self) -> io::Result<CString> {
         let buf: [libc::c_char; libc::IFNAMSIZ] =
             getsockopt(self, libc::SOL_SOCKET, libc::SO_BINDTODEVICE)?;
         let s: &[u8] = unsafe { core::slice::from_raw_parts(buf.as_ptr() as *const u8, buf.len()) };
-        let ifrname = CStr::from_bytes_until_nul(s).unwrap();
-        Ok(ifrname)
+        let name = CStr::from_bytes_until_nul(s).unwrap();
+        Ok(CString::new(name.to_bytes()).unwrap())
     }
 
     #[cfg(any(target_os = "linux", target_os = "haiku", target_os = "vxworks"))]
     pub fn set_todevice(&self, ifrname: &CStr) -> io::Result<()> {
+        let istr = ifrname.to_bytes();
+
+        if istr.len() >= libc::IFNAMSIZ {
+            return Err(io::Error::from_raw_os_error(libc::ENAMETOOLONG));
+        }
+
         let mut buf = [0; libc::IFNAMSIZ];
-        for (src, dst) in ifrname.to_bytes().iter().zip(&mut buf[..libc::IFNAMSIZ - 1]) {
+        for (src, dst) in istr.iter().zip(&mut buf[..libc::IFNAMSIZ - 1]) {
             *dst = *src as libc::c_char;
         }
         setsockopt(self, libc::SOL_SOCKET, libc::SO_BINDTODEVICE, buf)