From 7df6ab214908817073a346bcf06d776cfbe31bde Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sb@m-labs.hk>
Date: Sun, 7 Jun 2020 21:30:33 +0800
Subject: [PATCH] rpc: use async-recursion

---
 src/Cargo.lock         | 12 ++++++++++++
 src/runtime/Cargo.toml |  1 +
 src/runtime/src/rpc.rs | 17 ++++++++++-------
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/src/Cargo.lock b/src/Cargo.lock
index 58e773f..8a96b87 100644
--- a/src/Cargo.lock
+++ b/src/Cargo.lock
@@ -1,5 +1,16 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+[[package]]
+name = "async-recursion"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e5444eec77a9ec2bfe4524139e09195862e981400c4358d3b760cae634e4c4ee"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.0.0"
@@ -337,6 +348,7 @@ checksum = "bd7a31eed1591dcbc95d92ad7161908e72f4677f8fabf2a32ca49b4237cbf211"
 name = "runtime"
 version = "0.1.0"
 dependencies = [
+ "async-recursion",
  "byteorder",
  "core_io",
  "cslice",
diff --git a/src/runtime/Cargo.toml b/src/runtime/Cargo.toml
index 1cd6c66..624fc16 100644
--- a/src/runtime/Cargo.toml
+++ b/src/runtime/Cargo.toml
@@ -18,6 +18,7 @@ core_io = { version = "0.1", features = ["alloc", "collections"] }
 byteorder = { version = "1.3", default-features = false }
 void = { version = "1", default-features = false }
 futures = { version = "0.3", default-features = false, features = ["async-await"] }
+async-recursion = "0.3"
 libboard_zynq = { git = "https://git.m-labs.hk/M-Labs/zc706.git" }
 libsupport_zynq = { git = "https://git.m-labs.hk/M-Labs/zc706.git" }
 libcortex_a9 = { git = "https://git.m-labs.hk/M-Labs/zc706.git" }
diff --git a/src/runtime/src/rpc.rs b/src/runtime/src/rpc.rs
index fbaa209..ff7aa86 100644
--- a/src/runtime/src/rpc.rs
+++ b/src/runtime/src/rpc.rs
@@ -2,15 +2,18 @@ use core::str;
 use cslice::{CSlice, CMutSlice};
 use log::debug;
 
+use core_io::{Write, Error};
 use libboard_zynq::smoltcp;
 use libasync::smoltcp::TcpStream;
-use core_io::{Write, Error};
+use alloc::boxed::Box;
+use async_recursion::async_recursion;
 
 use crate::proto_core_io::ProtoWrite;
 use crate::proto_async;
 use self::tag::{Tag, TagIterator, split_tag};
 
-async unsafe fn recv_value(stream: &TcpStream, tag: Tag<'_>, data: &mut *mut (),
+#[async_recursion(?Send)]
+async unsafe fn recv_value(stream: &TcpStream, tag: Tag<'async_recursion>, data: &mut *mut (),
                            alloc: &dyn Fn(usize) -> *mut ())
                           -> Result<(), smoltcp::Error>
 {
@@ -51,7 +54,7 @@ async unsafe fn recv_value(stream: &TcpStream, tag: Tag<'_>, data: &mut *mut (),
             let mut it = it.clone();
             for _ in 0..arity {
                 let tag = it.next().expect("truncated tag");
-                //TODO: recv_value(reader, tag, data, alloc)?
+                recv_value(stream, tag, data, alloc).await?;
             }
             Ok(())
         }
@@ -65,16 +68,16 @@ async unsafe fn recv_value(stream: &TcpStream, tag: Tag<'_>, data: &mut *mut (),
 
                 let mut data = (*ptr).elements;
                 for _ in 0..(*ptr).length as usize {
-                    //TODO: recv_value(reader, tag, &mut data, alloc).await?
+                    recv_value(stream, tag, &mut data, alloc).await?
                 }
                 Ok(())
             })
         }
         Tag::Range(it) => {
             let tag = it.clone().next().expect("truncated tag");
-            /*TODO: recv_value(reader, tag, data, alloc).await?;
-            recv_value(reader, tag, data, alloc).await?;
-            recv_value(reader, tag, data, alloc).await?;*/
+            recv_value(stream, tag, data, alloc).await?;
+            recv_value(stream, tag, data, alloc).await?;
+            recv_value(stream, tag, data, alloc).await?;
             Ok(())
         }
         Tag::Keyword(_) => unreachable!(),