1 files changed, 149 insertions, 0 deletions
diff --git a/vendor/parking_lot_core-0.8.6/src/thread_parker/windows/waitaddress.rs b/vendor/parking_lot_core-0.8.6/src/thread_parker/windows/waitaddress.rs
new file mode 100644
index 000000000..862c5c652
--- /dev/null
+++ b/vendor/parking_lot_core-0.8.6/src/thread_parker/windows/waitaddress.rs
@@ -0,0 +1,149 @@
+// 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::{
+    mem,
+    sync::atomic::{AtomicUsize, Ordering},
+};
+use instant::Instant;
+use winapi::{
+    shared::{
+        basetsd::SIZE_T,
+        minwindef::{BOOL, DWORD, FALSE, TRUE},
+        winerror::ERROR_TIMEOUT,
+    },
+    um::{
+        errhandlingapi::GetLastError,
+        libloaderapi::{GetModuleHandleA, GetProcAddress},
+        winbase::INFINITE,
+        winnt::{LPCSTR, PVOID},
+    },
+};
+
+#[allow(non_snake_case)]
+pub struct WaitAddress {
+    WaitOnAddress: extern "system" fn(
+        Address: PVOID,
+        CompareAddress: PVOID,
+        AddressSize: SIZE_T,
+        dwMilliseconds: DWORD,
+    ) -> BOOL,
+    WakeByAddressSingle: extern "system" fn(Address: PVOID),
+}
+
+impl WaitAddress {
+    #[allow(non_snake_case)]
+    pub fn create() -> Option<WaitAddress> {
+        unsafe {
+            // MSDN claims that that WaitOnAddress and WakeByAddressSingle are
+            // located in kernel32.dll, but they are lying...
+            let synch_dll =
+                GetModuleHandleA(b"api-ms-win-core-synch-l1-2-0.dll\0".as_ptr() as LPCSTR);
+            if synch_dll.is_null() {
+                return None;
+            }
+
+            let WaitOnAddress = GetProcAddress(synch_dll, b"WaitOnAddress\0".as_ptr() as LPCSTR);
+            if WaitOnAddress.is_null() {
+                return None;
+            }
+            let WakeByAddressSingle =
+                GetProcAddress(synch_dll, b"WakeByAddressSingle\0".as_ptr() as LPCSTR);
+            if WakeByAddressSingle.is_null() {
+                return None;
+            }
+            Some(WaitAddress {
+                WaitOnAddress: mem::transmute(WaitOnAddress),
+                WakeByAddressSingle: mem::transmute(WakeByAddressSingle),
+            })
+        }
+    }
+
+    #[inline]
+    pub fn prepare_park(&'static self, key: &AtomicUsize) {
+        key.store(1, Ordering::Relaxed);
+    }
+
+    #[inline]
+    pub fn timed_out(&'static self, key: &AtomicUsize) -> bool {
+        key.load(Ordering::Relaxed) != 0
+    }
+
+    #[inline]
+    pub fn park(&'static self, key: &AtomicUsize) {
+        while key.load(Ordering::Acquire) != 0 {
+            let r = self.wait_on_address(key, INFINITE);
+            debug_assert!(r == TRUE);
+        }
+    }
+
+    #[inline]
+    pub fn park_until(&'static self, key: &AtomicUsize, timeout: Instant) -> bool {
+        while key.load(Ordering::Acquire) != 0 {
+            let now = Instant::now();
+            if timeout <= now {
+                return false;
+            }
+            let diff = timeout - now;
+            let timeout = diff
+                .as_secs()
+                .checked_mul(1000)
+                .and_then(|x| x.checked_add((diff.subsec_nanos() as u64 + 999999) / 1000000))
+                .map(|ms| {
+                    if ms > <DWORD>::max_value() as u64 {
+                        INFINITE
+                    } else {
+                        ms as DWORD
+                    }
+                })
+                .unwrap_or(INFINITE);
+            if self.wait_on_address(key, timeout) == FALSE {
+                debug_assert_eq!(unsafe { GetLastError() }, ERROR_TIMEOUT);
+            }
+        }
+        true
+    }
+
+    #[inline]
+    pub fn unpark_lock(&'static self, key: &AtomicUsize) -> UnparkHandle {
+        // We don't need to lock anything, just clear the state
+        key.store(0, Ordering::Release);
+
+        UnparkHandle {
+            key: key,
+            waitaddress: self,
+        }
+    }
+
+    #[inline]
+    fn wait_on_address(&'static self, key: &AtomicUsize, timeout: DWORD) -> BOOL {
+        let cmp = 1usize;
+        (self.WaitOnAddress)(
+            key as *const _ as PVOID,
+            &cmp as *const _ as PVOID,
+            mem::size_of::<usize>() as SIZE_T,
+            timeout,
+        )
+    }
+}
+
+// Handle for a thread that is about to be unparked. We need to mark the thread
+// as unparked while holding the queue lock, but we delay the actual unparking
+// until after the queue lock is released.
+pub struct UnparkHandle {
+    key: *const AtomicUsize,
+    waitaddress: &'static WaitAddress,
+}
+
+impl UnparkHandle {
+    // Wakes up the parked thread. This should be called after the queue lock is
+    // released to avoid blocking the queue for too long.
+    #[inline]
+    pub fn unpark(self) {
+        (self.waitaddress.WakeByAddressSingle)(self.key as PVOID);
+    }
+}