Fix for possible spurious wakeups

Fixes #1

Author: Detegr

src/lib.rs

@@ -3,6 +3,8 @@
 #![cfg_attr(feature="nightly", feature(static_condvar))]
 #![cfg_attr(feature="nightly", feature(static_mutex))]
 
+use std::sync::atomic::Ordering;
+
 #[cfg(not(windows))]
 extern crate libc;
 #[cfg(windows)]
@@ -15,17 +17,21 @@ extern crate lazy_static;
 
 #[cfg(feature="nightly")]
 mod features {
+    use std::sync::atomic::{AtomicBool, ATOMIC_BOOL_INIT};
     use std::sync::{StaticCondvar, CONDVAR_INIT, StaticMutex, MUTEX_INIT};
     pub static CVAR: StaticCondvar = CONDVAR_INIT;
     pub static MUTEX: StaticMutex = MUTEX_INIT;
+    pub static DONE: AtomicBool = ATOMIC_BOOL_INIT;
 }
 #[cfg(not(feature="nightly"))]
 mod features {
+    use std::sync::atomic::{AtomicBool, ATOMIC_BOOL_INIT};
     use std::sync::{Condvar, Mutex};
     lazy_static! {
         pub static ref CVAR: Condvar = Condvar::new();
         pub static ref MUTEX: Mutex<bool> = Mutex::new(false);
     }
+    pub static DONE: AtomicBool = ATOMIC_BOOL_INIT;
 }
 use self::features::*;
 
@@ -35,9 +41,11 @@ mod platform {
     use libc::types::os::common::posix01::sighandler_t;
     use libc::consts::os::posix88::SIGINT;
     use libc::funcs::posix01::signal::signal;
+    use std::sync::atomic::Ordering;
 
     #[repr(C)]
     pub fn handler(_: c_int) {
+        super::features::DONE.store(true, Ordering::Relaxed);
         super::features::CVAR.notify_all();
     }
     #[inline]
@@ -49,8 +57,10 @@ mod platform {
 mod platform {
     use kernel32::SetConsoleCtrlHandler;
     use winapi::{BOOL, DWORD, TRUE};
+    use std::sync::atomic::Ordering;
 
     pub unsafe extern "system" fn handler(_: DWORD) -> BOOL {
+        super::features::DONE.store(true, Ordering::Relaxed);
         super::features::CVAR.notify_all();
         TRUE
     }
@@ -75,7 +85,9 @@ impl CtrlC {
         }
         ::std::thread::spawn(move || {
             loop {
-                let _ = CVAR.wait(MUTEX.lock().unwrap());
+                if !DONE.load(Ordering::Relaxed) {
+                    let _ = CVAR.wait(MUTEX.lock().unwrap());
+                }
                 user_handler();
             }
         });