rust/src/libstd/sys/common/thread_info.rs
Alex Crichton d08600b189 std: Move the panic flag to its own thread local
This flag is somewhat tied to the `unwind` module rather than the `thread_info`
module, so this commit moves it into that module as well as allowing the same OS
thread to call `unwind::try` multiple times. Previously once a thread panicked
its panic flag was never reset, even after exiting the panic handler.
2014-12-18 23:35:52 -08:00

69 lines
2.1 KiB
Rust

// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use core::prelude::*;
use thread::Thread;
use cell::RefCell;
use string::String;
struct ThreadInfo {
// This field holds the known bounds of the stack in (lo, hi)
// form. Not all threads necessarily know their precise bounds,
// hence this is optional.
stack_bounds: (uint, uint),
stack_guard: uint,
thread: Thread,
}
thread_local!(static THREAD_INFO: RefCell<Option<ThreadInfo>> = RefCell::new(None))
impl ThreadInfo {
fn with<R>(f: |&mut ThreadInfo| -> R) -> R {
if THREAD_INFO.destroyed() {
panic!("Use of std::thread::Thread::current() is not possible after \
the thread's local data has been destroyed");
}
THREAD_INFO.with(|c| {
if c.borrow().is_none() {
*c.borrow_mut() = Some(ThreadInfo {
stack_bounds: (0, 0),
stack_guard: 0,
thread: NewThread::new(None),
})
}
f(c.borrow_mut().as_mut().unwrap())
})
}
}
pub fn current_thread() -> Thread {
ThreadInfo::with(|info| info.thread.clone())
}
pub fn stack_guard() -> uint {
ThreadInfo::with(|info| info.stack_guard)
}
pub fn set(stack_bounds: (uint, uint), stack_guard: uint, thread: Thread) {
THREAD_INFO.with(|c| assert!(c.borrow().is_none()));
THREAD_INFO.with(move |c| *c.borrow_mut() = Some(ThreadInfo{
stack_bounds: stack_bounds,
stack_guard: stack_guard,
thread: thread,
}));
}
// a hack to get around privacy restrictions; implemented by `std::thread::Thread`
pub trait NewThread {
fn new(name: Option<String>) -> Self;
}