Handles (#22)

* test coverage: make sure aliases to builtins get tested

* trivial support for handles

* add tests for handles

tests/atoms.rs

@@ -14,7 +14,10 @@ impl atoms::Atoms for WasiCtx {
         println!("INT FLOAT ARGS: {} {}", an_int, an_float);
         Ok(())
     }
-    fn double_int_return_float(&mut self, an_int: u32) -> Result<f32, types::Errno> {
+    fn double_int_return_float(
+        &mut self,
+        an_int: u32,
+    ) -> Result<types::AliasToFloat, types::Errno> {
         Ok((an_int as f32) * 2.0)
     }
 }
@@ -75,7 +78,7 @@ impl DoubleIntExercise {
             self.return_loc.ptr as i32,
         );
 
-        let return_val: GuestRef<f32> = guest_memory
+        let return_val: GuestRef<types::AliasToFloat> = guest_memory
             .ptr(self.return_loc.ptr)
             .expect("return loc ptr")
             .as_ref()

tests/atoms.witx

@@ -1,5 +1,7 @@
 (use "errno.witx")
 
+(typename $alias_to_float f32)
+
 (module $atoms
   (@interface func (export "int_float_args")
     (param $an_int u32)
@@ -8,5 +10,5 @@
   (@interface func (export "double_int_return_float")
     (param $an_int u32)
     (result $error $errno)
-    (result $doubled_it f32))
+    (result $doubled_it $alias_to_float))
 )

tests/handles.rs

@@ -0,0 +1,76 @@
+use proptest::prelude::*;
+use wiggle_runtime::{GuestError, GuestType};
+use wiggle_test::{impl_errno, HostMemory, MemArea, WasiCtx};
+
+const FD_VAL: u32 = 123;
+
+wiggle_generate::from_witx!({
+    witx: ["tests/handles.witx"],
+    ctx: WasiCtx,
+});
+
+impl_errno!(types::Errno);
+
+impl handle_examples::HandleExamples for WasiCtx {
+    fn fd_create(&mut self) -> Result<types::Fd, types::Errno> {
+        Ok(types::Fd::from(FD_VAL))
+    }
+    fn fd_consume(&mut self, fd: types::Fd) -> Result<(), types::Errno> {
+        println!("FD_CONSUME {}", fd);
+        if fd == types::Fd::from(FD_VAL) {
+            Ok(())
+        } else {
+            Err(types::Errno::InvalidArg)
+        }
+    }
+}
+
+#[derive(Debug)]
+struct HandleExercise {
+    pub return_loc: MemArea,
+}
+
+impl HandleExercise {
+    pub fn test(&self) {
+        let mut ctx = WasiCtx::new();
+        let mut host_memory = HostMemory::new();
+        let mut guest_memory = host_memory.guest_memory();
+
+        let e = handle_examples::fd_create(&mut ctx, &mut guest_memory, self.return_loc.ptr as i32);
+
+        assert_eq!(e, types::Errno::Ok.into(), "fd_create error");
+
+        let h_got: u32 = *guest_memory
+            .ptr(self.return_loc.ptr)
+            .expect("return ptr")
+            .as_ref()
+            .expect("return ref_mut");
+
+        assert_eq!(h_got, 123, "fd_create return val");
+
+        let e = handle_examples::fd_consume(&mut ctx, &mut guest_memory, h_got as i32);
+
+        assert_eq!(e, types::Errno::Ok.into(), "fd_consume error");
+
+        let e = handle_examples::fd_consume(&mut ctx, &mut guest_memory, h_got as i32 + 1);
+
+        assert_eq!(
+            e,
+            types::Errno::InvalidArg.into(),
+            "fd_consume invalid error"
+        );
+    }
+
+    pub fn strat() -> BoxedStrategy<Self> {
+        (HostMemory::mem_area_strat(types::Fd::size()))
+            .prop_map(|return_loc| HandleExercise { return_loc })
+            .boxed()
+    }
+}
+
+proptest! {
+    #[test]
+    fn handle_exercise(e in HandleExercise::strat()) {
+        e.test()
+    }
+}

tests/handles.witx

@@ -0,0 +1,12 @@
+(use "errno.witx")
+
+(typename $fd (handle))
+
+(module $handle_examples
+  (@interface func (export "fd_create")
+    (result $error $errno)
+    (result $fd $fd))
+  (@interface func (export "fd_consume")
+    (param $fd $fd)
+    (result $error $errno))
+)