CHANGELOG entry

Author: devnexen

CHANGELOG.md

@@ -67,6 +67,8 @@ This project adheres to [Semantic Versioning](https://semver.org/).
   ([#2097](https://github.com/nix-rust/nix/pull/2097))
 - Add the ability to set `kevent_flags` on `SigEvent`.
   ([#1731](https://github.com/nix-rust/nix/pull/1731))
+- Added `F_GETPATH` FcntlFlags entry on Apple/NetBSD/DragonflyBSD for `::nix::fcntl`.
+  ([#2142](https://github.com/nix-rust/nix/pull/2142))
 
 ### Changed
 

src/fcntl.rs

@@ -1,6 +1,13 @@
 use crate::errno::Errno;
 use libc::{self, c_char, c_int, c_uint, size_t, ssize_t};
 use std::ffi::OsString;
+#[cfg(any(
+    target_os = "netbsd",
+    target_os = "macos",
+    target_os = "ios",
+    target_os = "dragonfly",
+))]
+use std::ffi::CStr;
 #[cfg(not(target_os = "redox"))]
 use std::os::raw;
 use std::os::unix::ffi::OsStringExt;
@@ -561,12 +568,10 @@ pub fn fcntl(fd: RawFd, arg: FcntlArg) -> Result<c_int> {
             #[cfg(any(target_os = "dragonfly", target_os = "netbsd", target_os = "macos", target_os = "ios"))]
             F_GETPATH(path) => {
                 let mut buffer = vec![0; libc::PATH_MAX as usize];
-                let res = libc::fcntl(fd, libc::F_GETPATH, buffer.as_ptr());
+                let res = libc::fcntl(fd, libc::F_GETPATH, buffer.as_mut_ptr());
                 let ok_res = Errno::result(res)?;
-                let len = buffer.iter().position(|b| *b == 0).unwrap();
-                buffer.truncate(len as usize);
-                buffer.shrink_to_fit();
-                *path = PathBuf::from(OsString::from_vec(buffer));
+                let optr = CStr::from_bytes_until_nul(&mut buffer).unwrap();
+                *path = PathBuf::from(OsString::from(optr.to_str().unwrap()));
                 ok_res
             },
         }

test/test_fcntl.rs

@@ -582,6 +582,10 @@ mod test_apple_netbsd {
         let res =
             fcntl(fd, FcntlArg::F_GETPATH(&mut path)).expect("get path failed");
         assert_ne!(res, -1);
-        assert_eq!(path, tmp.path());
+        // We purposely check the canonical names for equality checks.
+        // The left operand tend to have `/private/var` whereas the right does not contains
+        // the `/private` part even tough in practice they lead to the same file, indeed
+        // `/var` is a symlink to `/private/var`.
+        assert_eq!(path.as_path().canonicalize().unwrap(), tmp.path().canonicalize().unwrap());
     }
 }