src/libstd/sys_common/thread.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 use alloc::boxed::FnBox;
  12 use env;
  13 use sync::atomic::{self, Ordering};
  14 use sys::stack_overflow;
  15 use sys::thread as imp;
  16
  17 #[allow(dead_code)]
  18 pub unsafe fn start_thread(main: *mut u8) {
  19     // Next, set up our stack overflow handler which may get triggered if we run
  20     // out of stack.
  21     let _handler = stack_overflow::Handler::new();
  22
  23     // Finally, let's run some code.
  24     Box::from_raw(main as *mut Box<FnBox()>)()
  25 }
  26
  27 pub fn min_stack() -> usize {
  28     static MIN: atomic::AtomicUsize = atomic::AtomicUsize::new(0);
  29     match MIN.load(Ordering::SeqCst) {
  30         0 => {}
  31         n => return n - 1,
  32     }
  33     let amt = env::var("RUST_MIN_STACK").ok().and_then(|s| s.parse().ok());
  34     let amt = amt.unwrap_or(imp::DEFAULT_MIN_STACK_SIZE);
  35
  36     // 0 is our sentinel value, so ensure that we'll never see 0 after
  37     // initialization has run
  38     MIN.store(amt + 1, Ordering::SeqCst);
  39     amt
  40 }