From c59772dca3bcea7d53e527bbe24dbf9dd2ed76b4 Mon Sep 17 00:00:00 2001
From: pca006132 <john.lck40@gmail.com>
Date: Mon, 6 Jul 2020 15:34:49 +0800
Subject: [PATCH] Exception handling: Implemented RPC exception.

---
 examples/exception.py     | 28 +++++++++++++++++++++++-----
 src/runtime/src/comms.rs  |  4 +++-
 src/runtime/src/kernel.rs | 28 ++++++++++++++++++++++++----
 3 files changed, 50 insertions(+), 10 deletions(-)

diff --git a/examples/exception.py b/examples/exception.py
index ec06741a..1745220d 100644
--- a/examples/exception.py
+++ b/examples/exception.py
@@ -1,20 +1,38 @@
 from artiq.experiment import *
+from artiq.language.core import TerminationRequested
 
 class ExceptionDemo(EnvExperiment):
     def build(self):
         self.setattr_device("core")
         self.setattr_device("led0")
 
+    def foo(self):
+        print("raise error")
+        raise Exception
+
+    def termination(self):
+        raise TerminationRequested
+
+    @rpc
+    def remote(self):
+        raise Exception
+
     @kernel
     def run(self):
         self.core.reset()
-        print("OK!")
         try:
             try:
-                raise Exception
+                self.foo()
             except ValueError as e:
-                print("re-raise")
-                raise e
+                print("should not trigger this")
         except:
-            print("error")
+            print("catch all")
+
+        try:
+            self.remote()
+        except:
+            print("Error!")
+
+        print("Uncaught error at last")
+        self.termination()
 
diff --git a/src/runtime/src/comms.rs b/src/runtime/src/comms.rs
index 5642ad3d..db9445e6 100644
--- a/src/runtime/src/comms.rs
+++ b/src/runtime/src/comms.rs
@@ -171,7 +171,9 @@ async fn handle_run_kernel(stream: &TcpStream, control: &Rc<RefCell<kernel::Cont
                             let line =     read_i32(stream).await?;
                             let column =   read_i32(stream).await?;
                             let function = read_string(stream, 16384).await?;
-                            control.tx.async_send(kernel::Message::RpcRecvReply(Err(()))).await;
+                            control.tx.async_send(kernel::Message::RpcRecvReply(Err(kernel::RPCException {
+                                name, message, param, file, line, column, function
+                            }))).await;
                         },
                         _ => {
                             error!("unexpected RPC request from host: {:?}", host_request);
diff --git a/src/runtime/src/kernel.rs b/src/runtime/src/kernel.rs
index 5a96324a..8539b210 100644
--- a/src/runtime/src/kernel.rs
+++ b/src/runtime/src/kernel.rs
@@ -1,7 +1,7 @@
 use core::{ptr, mem};
 use log::{debug, info, error};
-use alloc::{vec::Vec, sync::Arc};
-use cslice::CSlice;
+use alloc::{vec::Vec, sync::Arc, string::String};
+use cslice::{CSlice, AsCSlice};
 
 use libcortex_a9::{enable_fpu, cache::dcci_slice, mutex::Mutex, sync_channel::{self, sync_channel}};
 use libsupport_zynq::boot::Core1;
@@ -11,6 +11,16 @@ use crate::eh_artiq;
 use crate::rpc;
 use crate::rtio;
 
+#[derive(Debug)]
+pub struct RPCException {
+    pub name: String,
+    pub message: String,
+    pub param: [i64; 3],
+    pub file: String,
+    pub line: i32,
+    pub column: i32,
+    pub function: String
+}
 
 #[derive(Debug)]
 pub enum Message {
@@ -22,7 +32,7 @@ pub enum Message {
     KernelException(&'static eh_artiq::Exception<'static>, &'static [usize]),
     RpcSend { is_async: bool, data: Arc<Vec<u8>> },
     RpcRecvRequest(*mut ()),
-    RpcRecvReply(Result<usize, ()>),
+    RpcRecvReply(Result<usize, RPCException>),
 }
 
 static CHANNEL_0TO1: Mutex<Option<sync_channel::Receiver<Message>>> = Mutex::new(None);
@@ -150,7 +160,17 @@ extern fn rpc_recv(slot: *mut ()) -> usize {
     let reply = core1_rx.recv();
     match *reply {
         Message::RpcRecvReply(Ok(alloc_size)) => alloc_size,
-        Message::RpcRecvReply(Err(_)) => unimplemented!(),
+        Message::RpcRecvReply(Err(exception)) => unsafe {
+            eh_artiq::raise(&eh_artiq::Exception {
+                name:     exception.name.as_bytes().as_c_slice(),
+                file:     exception.file.as_bytes().as_c_slice(),
+                line:     exception.line as u32,
+                column:   exception.column as u32,
+                function: exception.function.as_bytes().as_c_slice(),
+                message:  exception.message.as_bytes().as_c_slice(),
+                param:    exception.param
+            })
+        },
         _ => panic!("received unexpected reply to RpcRecvRequest: {:?}", reply)
     }
 }