std::thread: adding get_name haiku implementation.

follow-up #123233

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

@@ -257,14 +257,32 @@ impl Thread {
  CString::new(name).ok()
  }
 
+ #[cfg(target_os = "haiku")]
+ pub fn get_name() -> Option<CString> {
+ unsafe {
+ let mut tinfo = mem::MaybeUninit::<libc::thread_info>::uninit();
+ // See BeOS teams group and threads api.
+ // https://www.haiku-os.org/legacy-docs/bebook/TheKernelKit_ThreadsAndTeams_Overview.html
+ let thread_self = libc::find_thread(ptr::null_mut());
+ let res = libc::get_thread_info(thread_self, tinfo.as_mut_ptr());
+ if res != libc::B_OK {
+ return None;
+ }
+ let info = tinfo.assume_init();
+ let name = slice::from_raw_parts(info.name.as_ptr() as *const u8, info.name.len());
+ CStr::from_bytes_until_nul(name).map(CStr::to_owned).ok()
+ }
+ }
+
  #[cfg(not(any(
  target_os = "linux",
  target_os = "freebsd",
  target_os = "netbsd",
  target_os = "macos",
  target_os = "ios",
  target_os = "tvos",
- target_os = "watchos"
+ target_os = "watchos",
+ target_os = "haiku"
  )))]
  pub fn get_name() -> Option<CString> {
  None