feat(examples): Add example returning references (#256)

Cargo.toml

@@ -8,6 +8,8 @@ license = "GPL-3.0"
 resolver = "2"
 members = [
     "client-gen",
+    "examples/references/app",
+    "examples/references/wasm",
     "examples/no-svcs-prog/app",
     "examples/no-svcs-prog/wasm",
     "examples/puppeteer/app",

examples/references/README.md

@@ -0,0 +1,3 @@
+# references
+
+This program demostrates how to return references instead of owned types

examples/references/app/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "references-app"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+gstd = { workspace = true, features = ["debug"] }
+sails-rtl.workspace = true

examples/references/app/src/lib.rs

@@ -0,0 +1,44 @@
+#![no_std]
+
+use core::ptr::addr_of;
+
+use gstd::prelude::*;
+use sails_rtl::gstd::gservice;
+
+static mut COUNTER: Counter = Counter { count: 0 };
+static mut BYTES: Vec<u8> = Vec::new();
+
+#[derive(Debug, Encode, Decode, TypeInfo)]
+#[codec(crate = sails_rtl::scale_codec)]
+#[scale_info(crate = sails_rtl::scale_info)]
+pub struct Counter {
+    count: u32,
+}
+
+#[derive(Default)]
+pub struct ReferenceService;
+
+#[gservice]
+impl ReferenceService {
+    pub const fn new() -> Self {
+        Self
+    }
+
+    pub fn baked(&self) -> &'static str {
+        "Static str!"
+    }
+
+    pub fn incr(&mut self) -> &'static Counter {
+        unsafe {
+            COUNTER.count += 1;
+            &*addr_of!(COUNTER)
+        }
+    }
+
+    pub fn add_byte(&mut self, byte: u8) -> &'static [u8] {
+        unsafe {
+            BYTES.push(byte);
+            &*addr_of!(BYTES)
+        }
+    }
+}

examples/references/wasm/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "references"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+gstd.workspace = true
+sails-rtl.workspace = true
+references-app = { path = "../app" }
+
+[build-dependencies]
+gwasm-builder.workspace = true
+sails-idl-gen.workspace = true
+references-app = { path = "../app" }

examples/references/wasm/build.rs

@@ -0,0 +1,15 @@
+use references_app::ReferenceService;
+use sails_idl_gen::service;
+use std::{env, fs::File, path::PathBuf};
+
+fn main() {
+    gwasm_builder::build();
+
+    let manifest_dir_path = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+
+    let idl_file_path = manifest_dir_path.join("references.idl");
+
+    let idl_file = File::create(idl_file_path).unwrap();
+
+    service::generate_idl::<ReferenceService>(idl_file).unwrap();
+}

examples/references/wasm/references.idl

@@ -0,0 +1,10 @@
+type Counter = struct {
+  count: u32,
+};
+
+service {
+  AddByte : (byte: u8) -> vec u8;
+  Incr : () -> Counter;
+  query Baked : () -> str;
+};
+

examples/references/wasm/src/lib.rs

@@ -0,0 +1,14 @@
+#![no_std]
+
+use references_app::ReferenceService;
+use sails_rtl::gstd::{msg, services::Service};
+
+#[gstd::async_main]
+async fn main() {
+    let input_bytes = msg::load_bytes().expect("Failed to read input");
+    let output_bytes = ReferenceService::new()
+        .expose(msg::id().into(), &[1, 2, 3])
+        .handle(&input_bytes)
+        .await;
+    msg::reply_bytes(output_bytes, 0).expect("Failed to send output");
+}