src/libstd/sys_common/thread_info.rs

   1 #![allow(dead_code)] // stack_guard isn't used right now on all platforms
   2
   3 use crate::cell::RefCell;
   4 use crate::sys::thread::guard::Guard;
   5 use crate::thread::Thread;
   6
   7 struct ThreadInfo {
   8     stack_guard: Option<Guard>,
   9     thread: Thread,
  10 }
  11
  12 thread_local! { static THREAD_INFO: RefCell<Option<ThreadInfo>> = RefCell::new(None) }
  13
  14 impl ThreadInfo {
  15     fn with<R, F>(f: F) -> Option<R> where F: FnOnce(&mut ThreadInfo) -> R {
  16         THREAD_INFO.try_with(move |c| {
  17             if c.borrow().is_none() {
  18                 *c.borrow_mut() = Some(ThreadInfo {
  19                     stack_guard: None,
  20                     thread: Thread::new(None),
  21                 })
  22             }
  23             f(c.borrow_mut().as_mut().unwrap())
  24         }).ok()
  25     }
  26 }
  27
  28 pub fn current_thread() -> Option<Thread> {
  29     ThreadInfo::with(|info| info.thread.clone())
  30 }
  31
  32 pub fn stack_guard() -> Option<Guard> {
  33     ThreadInfo::with(|info| info.stack_guard.clone()).and_then(|o| o)
  34 }
  35
  36 pub fn set(stack_guard: Option<Guard>, thread: Thread) {
  37     THREAD_INFO.with(|c| assert!(c.borrow().is_none()));
  38     THREAD_INFO.with(move |c| *c.borrow_mut() = Some(ThreadInfo{
  39         stack_guard,
  40         thread,
  41     }));
  42 }
  43
  44 pub fn reset_guard(stack_guard: Option<Guard>) {
  45     THREAD_INFO.with(move |c| c.borrow_mut().as_mut().unwrap().stack_guard = stack_guard);
  46 }