1 files changed, 121 insertions, 0 deletions
diff --git a/ctr-std/src/sys/redox/condvar.rs b/ctr-std/src/sys/redox/condvar.rs
new file mode 100644
index 0000000..2a611ed
--- /dev/null
+++ b/ctr-std/src/sys/redox/condvar.rs
@@ -0,0 +1,121 @@
+// Copyright 2016 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 cell::UnsafeCell;
+use intrinsics::{atomic_cxchg, atomic_load, atomic_xadd, atomic_xchg};
+use ptr;
+use time::Duration;
+
+use sys::mutex::{mutex_unlock, Mutex};
+use sys::syscall::{futex, TimeSpec, FUTEX_WAIT, FUTEX_WAKE, FUTEX_REQUEUE};
+
+pub struct Condvar {
+    lock: UnsafeCell<*mut i32>,
+    seq: UnsafeCell<i32>
+}
+
+impl Condvar {
+    pub const fn new() -> Condvar {
+        Condvar {
+            lock: UnsafeCell::new(ptr::null_mut()),
+            seq: UnsafeCell::new(0)
+        }
+    }
+
+    #[inline]
+    pub unsafe fn init(&self) {
+        *self.lock.get() = ptr::null_mut();
+        *self.seq.get() = 0;
+    }
+
+    #[inline]
+    pub fn notify_one(&self) {
+        unsafe {
+            let seq = self.seq.get();
+
+            atomic_xadd(seq, 1);
+
+            let _ = futex(seq, FUTEX_WAKE, 1, 0, ptr::null_mut());
+        }
+    }
+
+    #[inline]
+    pub fn notify_all(&self) {
+        unsafe {
+            let lock = self.lock.get();
+            let seq = self.seq.get();
+
+            if *lock == ptr::null_mut() {
+                return;
+            }
+
+            atomic_xadd(seq, 1);
+
+            let _ = futex(seq, FUTEX_REQUEUE, 1, ::usize::MAX, *lock);
+        }
+    }
+
+    #[inline]
+    unsafe fn wait_inner(&self, mutex: &Mutex, timeout_ptr: *const TimeSpec) -> bool {
+        let lock = self.lock.get();
+        let seq = self.seq.get();
+
+        if *lock != mutex.lock.get() {
+            if *lock != ptr::null_mut() {
+                panic!("Condvar used with more than one Mutex");
+            }
+
+            atomic_cxchg(lock as *mut usize, 0, mutex.lock.get() as usize);
+        }
+
+        mutex_unlock(*lock);
+
+        let seq_before = atomic_load(seq);
+
+        let _ = futex(seq, FUTEX_WAIT, seq_before, timeout_ptr as usize, ptr::null_mut());
+
+        let seq_after = atomic_load(seq);
+
+        while atomic_xchg(*lock, 2) != 0 {
+            let _ = futex(*lock, FUTEX_WAIT, 2, 0, ptr::null_mut());
+        }
+
+        seq_before != seq_after
+    }
+
+    #[inline]
+    pub fn wait(&self, mutex: &Mutex) {
+        unsafe {
+            assert!(self.wait_inner(mutex, ptr::null()));
+        }
+    }
+
+    #[inline]
+    pub fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool {
+        unsafe {
+            let timeout = TimeSpec {
+                tv_sec: dur.as_secs() as i64,
+                tv_nsec: dur.subsec_nanos() as i32
+            };
+
+            self.wait_inner(mutex, &timeout as *const TimeSpec)
+        }
+    }
+
+    #[inline]
+    pub unsafe fn destroy(&self) {
+        *self.lock.get() = ptr::null_mut();
+        *self.seq.get() = 0;
+    }
+}
+
+unsafe impl Send for Condvar {}
+
+unsafe impl Sync for Condvar {}