Merge #1849

1849: Add a Statfs::flags method r=rtzoeller a=asomers

It returns the mount flags on the BSDs.  On Linux, it returns a slightly different set of flags.

Co-authored-by: Alan Somers <asomers@gmail.com>

CHANGELOG.md

@@ -6,6 +6,10 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 ## [Unreleased] - ReleaseDate
 ### Added
 
+- Add `MntFlags` and `unmount` on all of the BSDs.
+  ([#1849](https://github.com/nix-rust/nix/pull/1849))
+- Added a 'Statfs::flags' method.
+  ([#1849](https://github.com/nix-rust/nix/pull/1849))
 - Added `NSFS_MAGIC` FsType on Linux and Android.
   ([#1829](https://github.com/nix-rust/nix/pull/1829))
 - Added `sched_getcpu` on platforms that support it.

Cargo.toml

@@ -27,7 +27,7 @@ targets = [
 ]
 
 [dependencies]
-libc = { version = "0.2.135", features = [ "extra_traits" ] }
+libc = { git = "https://github.com/rust-lang/libc", rev = "cc19b6f0801", features = [ "extra_traits" ] }
 bitflags = "1.1"
 cfg-if = "1.0"
 pin-utils = { version = "0.1.0", optional = true }

src/lib.rs

@@ -106,7 +106,6 @@ feature! {
     #[allow(missing_docs)]
     pub mod kmod;
 }
-#[cfg(any(target_os = "android", target_os = "freebsd", target_os = "linux"))]
 feature! {
     #![feature = "mount"]
     pub mod mount;

src/mount/bsd.rs

@@ -1,16 +1,22 @@
+#[cfg(target_os = "freebsd")]
 use crate::{
     Error,
+};
+use crate::{
     Errno,
     NixPath,
     Result,
 };
-use libc::{c_char, c_int, c_uint, c_void};
+#[cfg(target_os = "freebsd")]
+use libc::{c_char, c_uint, c_void};
+use libc::c_int;
+#[cfg(target_os = "freebsd")]
 use std::{
     borrow::Cow,
     ffi::{CString, CStr},
+    marker::PhantomData,
     fmt,
     io,
-    marker::PhantomData,
 };
 
 
@@ -110,12 +116,14 @@ libc_bitflags!(
 ///
 /// It wraps an [`Errno`], but also may contain an additional message returned
 /// by `nmount(2)`.
+#[cfg(target_os = "freebsd")]
 #[derive(Debug)]
 pub struct NmountError {
     errno: Error,
     errmsg: Option<String>
 }
 
+#[cfg(target_os = "freebsd")]
 impl NmountError {
     /// Returns the additional error string sometimes generated by `nmount(2)`.
     pub fn errmsg(&self) -> Option<&str> {
@@ -135,8 +143,10 @@ impl NmountError {
     }
 }
 
+#[cfg(target_os = "freebsd")]
 impl std::error::Error for NmountError {}
 
+#[cfg(target_os = "freebsd")]
 impl fmt::Display for NmountError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         if let Some(errmsg) = &self.errmsg {
@@ -147,13 +157,15 @@ impl fmt::Display for NmountError {
     }
 }
 
+#[cfg(target_os = "freebsd")]
 impl From<NmountError> for io::Error {
     fn from(err: NmountError) -> Self {
         err.errno.into()
     }
 }
 
 /// Result type of [`Nmount::nmount`].
+#[cfg(target_os = "freebsd")]
 pub type NmountResult = std::result::Result<(), NmountError>;
 
 /// Mount a FreeBSD file system.
@@ -425,13 +437,15 @@ impl<'a> Drop for Nmount<'a> {
 ///
 /// Useful flags include
 /// * `MNT_FORCE` -     Unmount even if still in use.
-/// * `MNT_BYFSID` -    `mountpoint` is not a path, but a file system ID
-///                     encoded as `FSID:val0:val1`, where `val0` and `val1`
-///                     are the contents of the `fsid_t val[]` array in decimal.
-///                     The file system that has the specified file system ID
-///                     will be unmounted.  See
-///                     [`statfs`](crate::sys::statfs::statfs) to determine the
-///                     `fsid`.
+#[cfg_attr(target_os = "freebsd", doc = "
+* `MNT_BYFSID` -    `mountpoint` is not a path, but a file system ID
+                    encoded as `FSID:val0:val1`, where `val0` and `val1`
+                    are the contents of the `fsid_t val[]` array in decimal.
+                    The file system that has the specified file system ID
+                    will be unmounted.  See
+                    [`statfs`](crate::sys::statfs::statfs) to determine the
+                    `fsid`.
+")]
 pub fn unmount<P>(mountpoint: &P, flags: MntFlags) -> Result<()>
     where P: ?Sized + NixPath
 {

src/sys/socket/mod.rs

@@ -272,14 +272,17 @@ libc_bitflags! {
         /// Sends or requests out-of-band data on sockets that support this notion
         /// (e.g., of type [`Stream`](enum.SockType.html)); the underlying protocol must also
         /// support out-of-band data.
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_OOB;
         /// Peeks at an incoming message. The data is treated as unread and the next
         /// [`recv()`](fn.recv.html)
         /// or similar function shall still return this data.
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_PEEK;
         /// Receive operation blocks until the full amount of data can be
         /// returned. The function may return smaller amount of data if a signal
         /// is caught, an error or disconnect occurs.
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_WAITALL;
         /// Enables nonblocking operation; if the operation would block,
         /// `EAGAIN` or `EWOULDBLOCK` is returned.  This provides similar
@@ -291,8 +294,10 @@ libc_bitflags! {
         /// which will affect all threads in
         /// the calling process and as well as other processes that hold
         /// file descriptors referring to the same open file description.
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_DONTWAIT;
         /// Receive flags: Control Data was discarded (buffer too small)
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_CTRUNC;
         /// For raw ([`Packet`](addr/enum.AddressFamily.html)), Internet datagram
         /// (since Linux 2.4.27/2.6.8),
@@ -302,15 +307,18 @@ libc_bitflags! {
         /// domain ([unix(7)](https://linux.die.net/man/7/unix)) sockets.
         ///
         /// For use with Internet stream sockets, see [tcp(7)](https://linux.die.net/man/7/tcp).
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_TRUNC;
         /// Terminates a record (when this notion is supported, as for
         /// sockets of type [`SeqPacket`](enum.SockType.html)).
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_EOR;
         /// This flag specifies that queued errors should be received from
         /// the socket error queue. (For more details, see
         /// [recvfrom(2)](https://linux.die.net/man/2/recvfrom))
         #[cfg(any(target_os = "android", target_os = "linux"))]
         #[cfg_attr(docsrs, doc(cfg(all())))]
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_ERRQUEUE;
         /// Set the `close-on-exec` flag for the file descriptor received via a UNIX domain
         /// file descriptor using the `SCM_RIGHTS` operation (described in
@@ -326,6 +334,7 @@ libc_bitflags! {
                   target_os = "netbsd",
                   target_os = "openbsd"))]
         #[cfg_attr(docsrs, doc(cfg(all())))]
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_CMSG_CLOEXEC;
         /// Requests not to send `SIGPIPE` errors when the other end breaks the connection.
         /// (For more details, see [send(2)](https://linux.die.net/man/2/send)).
@@ -340,6 +349,7 @@ libc_bitflags! {
                   target_os = "openbsd",
                   target_os = "solaris"))]
         #[cfg_attr(docsrs, doc(cfg(all())))]
+        #[allow(deprecated)]    // Suppress useless warnings from libc PR 2963
         MSG_NOSIGNAL;
     }
 }