tracing fixes in unix poll; add some missing debug impls

crates/wasi-common/src/entry.rs

@@ -18,6 +18,12 @@ impl EntryHandle {
     }
 }
 
+impl std::fmt::Debug for EntryHandle {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        f.debug_struct("EntryHandle").field("opaque", &()).finish()
+    }
+}
+
 impl From<Box<dyn Handle>> for EntryHandle {
     fn from(handle: Box<dyn Handle>) -> Self {
         Self(handle.into())

crates/wasi-common/src/poll.rs

@@ -9,6 +9,7 @@ pub(crate) struct ClockEventData {
     pub(crate) userdata: types::Userdata,
 }
 
+#[derive(Debug)]
 pub(crate) struct FdEventData {
     pub(crate) handle: EntryHandle,
     pub(crate) r#type: types::Eventtype,

crates/wasi-common/src/sys/unix/poll.rs

@@ -38,7 +38,10 @@ pub(crate) fn oneoff(
         let delay = timeout.delay / 1_000_000; // poll syscall requires delay to expressed in milliseconds
         delay.try_into().unwrap_or(libc::c_int::max_value())
     });
-    tracing::debug!("poll_oneoff poll_timeout = {:?}", poll_timeout);
+    tracing::debug!(
+        poll_timeout = tracing::field::debug(poll_timeout),
+        "poll_oneoff"
+    );
 
     let ready = loop {
         match poll(&mut poll_fds, poll_timeout) {
@@ -91,15 +94,17 @@ fn handle_fd_event(
     }
 
     for (fd_event, poll_fd) in ready_events {
-        tracing::debug!("poll_oneoff_handle_fd_event poll_fd = {:?}", poll_fd);
+        tracing::debug!(
+            poll_fd = tracing::field::debug(poll_fd),
+            poll_event = tracing::field::debug(&fd_event),
+            "poll_oneoff handle_fd_event"
+        );
 
         let revents = match poll_fd.revents() {
             Some(revents) => revents,
             None => continue,
         };
 
-        tracing::debug!("poll_oneoff_handle_fd_event revents = {:?}", revents);
-
         let nbytes = if fd_event.r#type == types::Eventtype::FdRead {
             query_nbytes(fd_event.handle)?
         } else {