wasm: Rust support

src/server/wasm/api.h

@@ -23,6 +23,7 @@ bool RegisterApiFunction(std::string_view name, Fn f, wasmtime::Linker* linker)
   auto args_signature = wasmtime::FuncType({wasmtime::ValKind::I32}, {});
 
   auto res = linker->func_new(module_name, name, args_signature, f);
+  linker->func_new("env", name, args_signature, f);
   return (bool)res;
 }
 

src/wasm_sdk/cpp/include/dragonfly.h

@@ -53,7 +53,7 @@ inline std::string_view call(std::initializer_list<std::string> arguments) {
 
 /* Private and NOT part of the public API */
 DF_EXPORT("provide_buffer")
-inline char* provide_buffer(size_t bytes) {
+inline char* provide_buffer(int32_t bytes) {
   call_buffer.resize(bytes);
   return call_buffer.data();
 }

src/wasm_sdk/rustw/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "rustw"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[lib]
+crate-type = ["cdylib"]

src/wasm_sdk/rustw/README.md

@@ -0,0 +1,3 @@
+https://github.com/bytecodealliance/cargo-wasi/tree/main
+
+then just run `cargo wasi build`

src/wasm_sdk/rustw/src/lib.rs

@@ -0,0 +1,39 @@
+use std::io::Write;
+
+extern "C" {
+    pub fn call(cmd: *const u8);
+}
+
+static mut BUFFER: Option<String> = None;
+
+pub fn run(command: &[&str]) -> String {
+    let mut bytes = Vec::<u8>::new();
+
+    unsafe {
+        bytes
+            .write(&std::mem::transmute::<i32, [u8; 4]>(command.len() as i32))
+            .unwrap();
+
+        for part in command {
+            bytes
+                .write(&std::mem::transmute::<i32, [u8; 4]>(part.len() as i32))
+                .unwrap();
+            bytes.write(part.as_bytes()).unwrap();
+        }
+
+        call(bytes.as_ptr());
+
+        BUFFER.take().unwrap()
+    }
+}
+
+#[no_mangle]
+pub unsafe fn provide_buffer(bytes: i32) -> *mut u8 {
+    BUFFER.insert(str::repeat(" ", bytes as usize)).as_mut_ptr()
+}
+
+#[no_mangle]
+pub fn my_fun() {
+    let res = run(&["GET", "A"]);
+    println!("Got {}", res);
+}