top: Swich some uses of libc to rustix

Cargo.toml

@@ -68,7 +68,7 @@ prettytable-rs = "0.10.0"
 rand = { version = "0.10.0" }
 ratatui = "0.30.0"
 regex = "1.10.4"
-rustix = { version = "1.1.2", features = ["fs", "process"] }
+rustix = { version = "1.1.2", features = ["fs", "process", "param"] }
 sysinfo = "0.38.0"
 tempfile = "3.10.1"
 terminal_size = "0.4.2"

src/uu/top/Cargo.toml

@@ -22,6 +22,7 @@ ratatui = { workspace = true, features = ["crossterm"] }
 sysinfo = { workspace = true }
 chrono = { workspace = true }
 bytesize = { workspace = true }
+rustix = { workspace = true }
 
 uu_vmstat = { path = "../vmstat" }
 uu_w = { path = "../w" }

src/uu/top/src/action.rs

@@ -5,15 +5,11 @@
 
 #[cfg(target_os = "linux")]
 pub(crate) fn renice(pid: u32, nice_value: i32) -> uucore::error::UResult<()> {
+    use rustix::process::{setpriority_process, Pid};
     use uucore::error::USimpleError;
-    use uucore::libc::{setpriority, PRIO_PROCESS};
 
-    let result = unsafe { setpriority(PRIO_PROCESS, pid, nice_value) };
-    if result == -1 {
-        Err(USimpleError::new(0, "Permission Denied"))
-    } else {
-        Ok(())
-    }
+    let pid = Pid::from_raw(pid as i32);
+    setpriority_process(pid, nice_value).map_err(|_| USimpleError::new(0, "Permission Denied"))
 }
 
 #[cfg(unix)]

src/uu/top/src/picker.rs

@@ -317,20 +317,11 @@ fn pr(_pid: u32, _stat: Stat) -> Box<dyn Column> {
 
 #[cfg(not(target_os = "windows"))]
 fn get_nice(pid: u32) -> i32 {
-    use nix::errno::Errno;
-    use uucore::libc::{getpriority, PRIO_PROCESS};
+    use rustix::process::{getpriority_process, Pid};
 
     // this is nice value, not priority value
-    let result = unsafe { getpriority(PRIO_PROCESS, pid) };
-
-    let result = if Errno::last() == Errno::UnknownErrno {
-        result
-    } else {
-        Errno::clear();
-        0
-    };
-
-    result as i32
+    let pid = Pid::from_raw(pid as i32);
+    getpriority_process(pid).unwrap_or(0)
 }
 
 #[cfg(not(target_os = "windows"))]
@@ -381,7 +372,7 @@ fn shr(pid: u32, _stat: Stat) -> Box<dyn Column> {
     let content = read_to_string(file).unwrap();
     let values = content.split_whitespace();
     if let Some(shared) = values.collect::<Vec<_>>().get(2) {
-        let page_size = unsafe { uucore::libc::sysconf(uucore::libc::_SC_PAGESIZE) };
+        let page_size = rustix::param::page_size();
         MemValue::new_boxed(shared.parse::<u64>().unwrap() * page_size as u64)
     } else {
         MemValue::new_boxed(0)