Finished middleware impl and made a CallTrace middleware

lib/middleware-common/src/call_trace.rs

@@ -0,0 +1,27 @@
+use wasmer_runtime_core::{
+    codegen::{Event, EventSink, FunctionMiddleware, InternalEvent},
+    module::ModuleInfo,
+};
+
+pub struct CallTrace;
+
+impl FunctionMiddleware for CallTrace {
+    type Error = String;
+    fn feed_event<'a, 'b: 'a>(
+        &mut self,
+        op: Event<'a, 'b>,
+        module_info: &ModuleInfo,
+        sink: &mut EventSink<'a, 'b>,
+    ) -> Result<(), Self::Error> {
+        match op {
+            Event::Internal(InternalEvent::FunctionBegin(id)) => {
+                sink.push(Event::Internal(InternalEvent::Bkpt(Box::new(move |_| {
+                    println!("func ({})", id);
+                }))))
+            }
+            _ => {}
+        }
+        sink.push(op);
+        Ok(())
+    }
+}

lib/middleware-common/src/lib.rs

@@ -0,0 +1,9 @@
+pub mod call_trace;
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn it_works() {
+        assert_eq!(2 + 2, 4);
+    }
+}