1 files changed, 139 insertions, 0 deletions
diff --git a/vendor/parking_lot_core-0.8.6/src/thread_parker/redox.rs b/vendor/parking_lot_core-0.8.6/src/thread_parker/redox.rs
new file mode 100644
index 000000000..cac06bcfe
--- /dev/null
+++ b/vendor/parking_lot_core-0.8.6/src/thread_parker/redox.rs
@@ -0,0 +1,139 @@
+// Copyright 2016 Amanieu d'Antras
+//
+// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
+// http://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::{
+    ptr,
+    sync::atomic::{AtomicI32, Ordering},
+};
+use instant::Instant;
+use std::thread;
+use syscall::{
+    call::futex,
+    data::TimeSpec,
+    error::{Error, EAGAIN, EFAULT, EINTR, ETIMEDOUT},
+    flag::{FUTEX_WAIT, FUTEX_WAKE},
+};
+
+const UNPARKED: i32 = 0;
+const PARKED: i32 = 1;
+
+// Helper type for putting a thread to sleep until some other thread wakes it up
+pub struct ThreadParker {
+    futex: AtomicI32,
+}
+
+impl super::ThreadParkerT for ThreadParker {
+    type UnparkHandle = UnparkHandle;
+
+    const IS_CHEAP_TO_CONSTRUCT: bool = true;
+
+    #[inline]
+    fn new() -> ThreadParker {
+        ThreadParker {
+            futex: AtomicI32::new(UNPARKED),
+        }
+    }
+
+    #[inline]
+    unsafe fn prepare_park(&self) {
+        self.futex.store(PARKED, Ordering::Relaxed);
+    }
+
+    #[inline]
+    unsafe fn timed_out(&self) -> bool {
+        self.futex.load(Ordering::Relaxed) != UNPARKED
+    }
+
+    #[inline]
+    unsafe fn park(&self) {
+        while self.futex.load(Ordering::Acquire) != UNPARKED {
+            self.futex_wait(None);
+        }
+    }
+
+    #[inline]
+    unsafe fn park_until(&self, timeout: Instant) -> bool {
+        while self.futex.load(Ordering::Acquire) != UNPARKED {
+            let now = Instant::now();
+            if timeout <= now {
+                return false;
+            }
+            let diff = timeout - now;
+            if diff.as_secs() > i64::max_value() as u64 {
+                // Timeout overflowed, just sleep indefinitely
+                self.park();
+                return true;
+            }
+            let ts = TimeSpec {
+                tv_sec: diff.as_secs() as i64,
+                tv_nsec: diff.subsec_nanos() as i32,
+            };
+            self.futex_wait(Some(ts));
+        }
+        true
+    }
+
+    #[inline]
+    unsafe fn unpark_lock(&self) -> UnparkHandle {
+        // We don't need to lock anything, just clear the state
+        self.futex.store(UNPARKED, Ordering::Release);
+
+        UnparkHandle { futex: self.ptr() }
+    }
+}
+
+impl ThreadParker {
+    #[inline]
+    fn futex_wait(&self, ts: Option<TimeSpec>) {
+        let ts_ptr = ts
+            .as_ref()
+            .map(|ts_ref| ts_ref as *const _)
+            .unwrap_or(ptr::null());
+        let r = unsafe {
+            futex(
+                self.ptr(),
+                FUTEX_WAIT,
+                PARKED,
+                ts_ptr as usize,
+                ptr::null_mut(),
+            )
+        };
+        match r {
+            Ok(r) => debug_assert_eq!(r, 0),
+            Err(Error { errno }) => {
+                debug_assert!(errno == EINTR || errno == EAGAIN || errno == ETIMEDOUT);
+            }
+        }
+    }
+
+    #[inline]
+    fn ptr(&self) -> *mut i32 {
+        &self.futex as *const AtomicI32 as *mut i32
+    }
+}
+
+pub struct UnparkHandle {
+    futex: *mut i32,
+}
+
+impl super::UnparkHandleT for UnparkHandle {
+    #[inline]
+    unsafe fn unpark(self) {
+        // The thread data may have been freed at this point, but it doesn't
+        // matter since the syscall will just return EFAULT in that case.
+        let r = futex(self.futex, FUTEX_WAKE, PARKED, 0, ptr::null_mut());
+        match r {
+            Ok(num_woken) => debug_assert!(num_woken == 0 || num_woken == 1),
+            Err(Error { errno }) => debug_assert_eq!(errno, EFAULT),
+        }
+    }
+}
+
+#[inline]
+pub fn thread_yield() {
+    thread::yield_now();
+}