DemesneGH commented on code in PR #178:
URL: 
https://github.com/apache/incubator-teaclave-trustzone-sdk/pull/178#discussion_r2034371745


##########
optee-utee/src/tee_parameter.rs:
##########
@@ -0,0 +1,302 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use crate::ParamType;
+use core::ops::{Index, IndexMut};
+use optee_utee_sys as raw;
+
+#[derive(Copy, Clone, Debug)]
+pub enum ParamIndex {
+    Arg0,
+    Arg1,
+    Arg2,
+    Arg3,
+}
+
+impl ParamIndex {
+    fn to_usize(self) -> usize {
+        match self {
+            ParamIndex::Arg0 => 0,
+            ParamIndex::Arg1 => 1,
+            ParamIndex::Arg2 => 2,
+            ParamIndex::Arg3 => 3,
+        }
+    }
+}
+
+enum ParamContent<'a> {
+    None,
+    MemrefInput {
+        buffer: &'a [u8],
+    },
+    MemrefOutput {
+        buffer: &'a mut [u8],
+        written: usize,
+    },
+    MemrefInout {
+        buffer: &'a mut [u8],
+        written: usize,
+    },
+    ValueInput {
+        a: u32,
+        b: u32,
+    },
+    ValueOutput {
+        a: u32,
+        b: u32,
+    },
+    ValueInout {
+        a: u32,
+        b: u32,
+    },
+}
+
+pub struct Param<'a> {
+    content: ParamContent<'a>,
+}
+
+impl<'a> Param<'a> {
+    fn new() -> Self {
+        Self {
+            content: ParamContent::None,
+        }
+    }
+
+    pub fn written_slice(&self) -> Option<&[u8]> {

Review Comment:
   
   > developers can easily convert the `Result` to `Option` using `ok()` or 
`err()` method.
   
   Yes it also works but follows a different design choice.
   
   In current strategy, we choose to return an Option to indicate whether a 
written slice is available, allowing developers to decide whether to raise an 
error.
   



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: dev-unsubscr...@teaclave.apache.org

For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@teaclave.apache.org
For additional commands, e-mail: dev-h...@teaclave.apache.org

Reply via email to