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use crate::*;
use bindings::{
Windows::Win32::SystemServices::{CreateEventW, SetEvent, WaitForSingleObject, HANDLE, PWSTR},
Windows::Win32::WindowsProgramming::CloseHandle,
};
/// A simple blocking waiter used by the generated bindings and should not be used directly.
pub struct Waiter(HANDLE);
pub struct WaiterSignaler(HANDLE);
impl Waiter {
pub fn new() -> (Waiter, WaiterSignaler) {
unsafe {
let handle = CreateEventW(std::ptr::null_mut(), true, false, PWSTR::default());
(Waiter(handle), WaiterSignaler(handle))
}
}
}
impl WaiterSignaler {
/// Signals the `Waiter`. This is unsafe because the lifetime of `WaiterSignaler` is not tied
/// to the lifetime of the `Waiter`. This is not possible in this case because the `Waiter`
/// is used to signal a WinRT async completion and the compiler doesn't know that the lifetime
/// of the delegate is bounded by the calling function.
pub unsafe fn signal(&self) {
// https://github.com/microsoft/windows-rs/pull/374#discussion_r535313344
SetEvent(self.0);
}
}
impl Drop for Waiter {
fn drop(&mut self) {
unsafe {
WaitForSingleObject(self.0, 0xFFFFFFFF);
CloseHandle(self.0);
}
}
}