stub in windows scheduler, get to some interesting errors

crates/wasi-c2/cap-std-sync/src/sched.rs

@@ -1,5 +1,7 @@
 #[cfg(unix)]
 pub use unix::*;
+#[cfg(windows)]
+pub use windows::*;
 
 #[cfg(unix)]
 mod unix {
@@ -7,10 +9,14 @@ mod unix {
     use std::convert::TryInto;
     use std::ops::Deref;
     use std::os::unix::io::{AsRawFd, RawFd};
-    use wasi_c2::file::WasiFile;
+    use wasi_c2::{
-    use wasi_c2::sched::subscription::{RwEventFlags, Subscription};
+        file::WasiFile,
-    use wasi_c2::sched::{Poll, WasiSched};
+        sched::{
-    use wasi_c2::Error;
+            subscription::{RwEventFlags, Subscription},
+            Poll, WasiSched,
+        },
+        Error,
+    };
     use yanix::poll::{PollFd, PollFlags};
 
     pub struct SyncSched;
@@ -126,3 +132,58 @@ mod unix {
         }
     }
 }
+
+#[cfg(windows)]
+mod windows {
+    use std::os::windows::io::{AsRawHandle, RawHandle};
+    use wasi_c2::{
+        file::WasiFile,
+        sched::{Poll, WasiSched},
+        Error,
+    };
+    pub struct SyncSched;
+
+    impl WasiSched for SyncSched {
+        fn poll_oneoff<'a>(&self, poll: &'a Poll<'a>) -> Result<(), Error> {
+            if poll.is_empty() {
+                return Ok(());
+            }
+            todo!()
+        }
+        fn sched_yield(&self) -> Result<(), Error> {
+            std::thread::yield_now();
+            Ok(())
+        }
+    }
+
+    fn wasi_file_raw_handle(f: &dyn WasiFile) -> Option<RawHandle> {
+        let a = f.as_any();
+        if a.is::<crate::file::File>() {
+            Some(
+                a.downcast_ref::<crate::file::File>()
+                    .unwrap()
+                    .as_raw_handle(),
+            )
+        } else if a.is::<crate::stdio::Stdin>() {
+            Some(
+                a.downcast_ref::<crate::stdio::Stdin>()
+                    .unwrap()
+                    .as_raw_handle(),
+            )
+        } else if a.is::<crate::stdio::Stdout>() {
+            Some(
+                a.downcast_ref::<crate::stdio::Stdout>()
+                    .unwrap()
+                    .as_raw_handle(),
+            )
+        } else if a.is::<crate::stdio::Stderr>() {
+            Some(
+                a.downcast_ref::<crate::stdio::Stderr>()
+                    .unwrap()
+                    .as_raw_handle(),
+            )
+        } else {
+            None
+        }
+    }
+}