1use super::*;
2
3pub struct Waiter(HANDLE);
4pub struct WaiterSignaler(HANDLE);
5unsafe impl Send for WaiterSignaler {}
6
7impl Waiter {
8 pub fn new() -> crate::Result<(Waiter, WaiterSignaler)> {
9 unsafe {
10 let handle: *mut c_void = CreateEventW(lpeventattributes:core::ptr::null(), bmanualreset:1, binitialstate:0, lpname:core::ptr::null());
11 if handle.is_null() {
12 Err(crate::Error::from_win32())
13 } else {
14 Ok((Waiter(handle), WaiterSignaler(handle)))
15 }
16 }
17 }
18}
19
20impl WaiterSignaler {
21 /// # Safety
22 /// Signals the `Waiter`. This is unsafe because the lifetime of `WaiterSignaler` is not tied
23 /// to the lifetime of the `Waiter`. This is not possible in this case because the `Waiter`
24 /// is used to signal a WinRT async completion and the compiler doesn't know that the lifetime
25 /// of the delegate is bounded by the calling function.
26 pub unsafe fn signal(&self) {
27 // https://github.com/microsoft/windows-rs/pull/374#discussion_r535313344
28 unsafe {
29 SetEvent(self.0);
30 }
31 }
32}
33
34impl Drop for Waiter {
35 fn drop(&mut self) {
36 unsafe {
37 WaitForSingleObject(self.0, dwmilliseconds:0xFFFFFFFF);
38 CloseHandle(self.0);
39 }
40 }
41}
42