Try to enhance no std support

Cargo.toml

@@ -39,6 +39,8 @@ bindings_header = "./crates/wamr-sys/wasm-micro-runtime/core/iwasm/include/wasm_
 component_dirs = ["./crates/wamr-sys/wasm-micro-runtime/build-scripts/esp-idf"]
 
 [features]
+default = ["std"]
+std = ["wamr-sys/std"]
 custom-section = ["wamr-sys/custom-section"]
 dump-call-stack = ["wamr-sys/dump-call-stack"]
 esp-idf = ["esp-idf-sys", "wamr-sys/esp-idf"]

src/function.rs

@@ -6,7 +6,9 @@
 //! an exported wasm function.
 //! get one via `Function::find_export_func()`
 
-use std::{ffi::CString, marker::PhantomData};
+use alloc::{ffi::CString, vec::Vec};
+use core::marker::PhantomData;
+
 use wamr_sys::{
     wasm_exec_env_t, wasm_func_get_result_count, wasm_func_get_result_types, wasm_function_inst_t,
     wasm_runtime_call_wasm, wasm_runtime_get_exception, wasm_runtime_get_exec_env_singleton,

src/helper.rs

@@ -3,8 +3,8 @@
  * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  */
 
-use std::ffi::{c_char, CStr};
-use std::string::String;
+use alloc::{string::{String, ToString}, vec::Vec};
+use core::ffi::{c_char, CStr};
 
 pub const DEFAULT_ERROR_BUF_SIZE: usize = 128;
 

src/host_function.rs

@@ -4,8 +4,9 @@
  */
 
 /// This is a wrapper of a host defined(Rust) function.
-use std::ffi::{c_void, CString};
-use std::ptr;
+
+use alloc::{ffi::CString, vec::Vec};
+use core::{ffi::c_void, ptr};
 
 use wamr_sys::NativeSymbol;
 

src/instance.rs

@@ -8,6 +8,7 @@
 
 #![allow(unused_variables)]
 
+use alloc::string::String;
 use core::{ffi::c_char, marker::PhantomData};
 
 use wamr_sys::{

src/lib.rs

@@ -68,12 +68,11 @@
 //!     runtime::Runtime, module::Module, instance::Instance, function::Function,
 //!     value::WasmValue, RuntimeError
 //! };
-//! use std::path::PathBuf;
 //!
 //! fn main() -> Result<(), RuntimeError> {
 //!     let runtime = Runtime::new()?;
 //!
-//!     let mut d = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
+//!     let mut d = std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"));
 //!     d.push("resources/test");
 //!     d.push("gcd_wasm32_wasi.wasm");
 //!
@@ -106,12 +105,18 @@
 //! The rust code to call the *add* function is like this:
 //!
 //! ```
+//! #![no_std]
+//!
+//! #[macro_use]
+//! extern crate alloc;
+//!
+//! use alloc::vec::Vec;
+//! use core::ffi::c_void;
+//!
 //! use wamr_rust_sdk::{
 //!     runtime::Runtime, module::Module, instance::Instance, function::Function,
 //!     value::WasmValue, RuntimeError
 //! };
-//! use std::path::PathBuf;
-//! use std::ffi::c_void;
 //!
 //! extern "C" fn extra() -> i32 {
 //!     100
@@ -123,10 +128,9 @@
 //!         .register_host_function("extra", extra as *mut c_void)
 //!         .build()?;
 //!
-//!     let mut d = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
-//!     d.push("resources/test");
-//!     d.push("add_extra_wasm32_wasi.wasm");
-//!     let module = Module::from_file(&runtime, d.as_path())?;
+//!     
+//!     let bytes = include_bytes!(concat!(env!("CARGO_MANIFEST_DIR"), "/resources/test/add_extra_wasm32_wasi.wasm"));
+//!     let module = Module::from_vec(&runtime, Vec::from(bytes), "add_extra")?;
 //!
 //!     let instance = Instance::new(&runtime, &module, 1024 * 64)?;
 //!
@@ -141,9 +145,13 @@
 //! ```
 //!
 
-use std::error;
-use std::fmt;
-use std::io;
+#![cfg_attr(all(not(test), not(feature = "std")), no_std)]
+
+#[macro_use]
+extern crate alloc;
+
+use alloc::string::String;
+use core::{error, fmt};
 pub use wamr_sys as sys;
 
 pub mod function;
@@ -168,6 +176,7 @@ pub enum RuntimeError {
     /// Runtime initialization error.
     InitializationFailure,
     /// file operation error. usually while loading(compilation) a .wasm
+    #[cfg(any(test, feature = "std"))]
     WasmFileFSError(std::io::Error),
     /// A compilation error. usually means that the .wasm file is invalid
     CompilationError(String),
@@ -184,6 +193,7 @@ impl fmt::Display for RuntimeError {
         match self {
             RuntimeError::NotImplemented => write!(f, "Not implemented"),
             RuntimeError::InitializationFailure => write!(f, "Runtime initialization failure"),
+            #[cfg(any(test, feature = "std"))]
             RuntimeError::WasmFileFSError(e) => write!(f, "Wasm file operation error: {}", e),
             RuntimeError::CompilationError(e) => write!(f, "Wasm compilation error: {}", e),
             RuntimeError::InstantiationFailure(e) => write!(f, "Wasm instantiation failure: {}", e),
@@ -200,14 +210,16 @@ impl fmt::Display for RuntimeError {
 impl error::Error for RuntimeError {
     fn source(&self) -> Option<&(dyn error::Error + 'static)> {
         match self {
+            #[cfg(any(test, feature = "std"))]
             RuntimeError::WasmFileFSError(e) => Some(e),
             _ => None,
         }
     }
 }
 
-impl From<io::Error> for RuntimeError {
-    fn from(e: io::Error) -> Self {
+#[cfg(any(test, feature = "std"))]
+impl From<std::io::Error> for RuntimeError {
+    fn from(e: std::io::Error) -> Self {
         RuntimeError::WasmFileFSError(e)
     }
 }

src/module.rs

@@ -4,28 +4,22 @@
  */
 
 //! .wasm compiled, in-memory representation
-//! get one via `Module::from_file()` or `Module::from_buf()`
+//! get one via `Module::from_file()` or `Module::from_vec()`
+
+use alloc::{ffi::CString, string::String, vec::Vec};
+use core::{ffi::c_char, marker::PhantomData, ptr};
 
-use crate::{
-    helper::error_buf_to_string, helper::DEFAULT_ERROR_BUF_SIZE, runtime::Runtime,
-    wasi_context::WasiCtx, RuntimeError,
-};
-use core::marker::PhantomData;
-use std::{
-    ffi::{c_char, CString},
-    fs::File,
-    io::Read,
-    path::Path,
-    ptr,
-    string::String,
-    vec::Vec,
-};
 use wamr_sys::{
     wasm_module_t, wasm_runtime_load, wasm_runtime_set_module_name,
     wasm_runtime_set_wasi_addr_pool, wasm_runtime_set_wasi_args,
     wasm_runtime_set_wasi_ns_lookup_pool, wasm_runtime_unload,
 };
 
+use crate::{
+    helper::error_buf_to_string, helper::DEFAULT_ERROR_BUF_SIZE, runtime::Runtime,
+    wasi_context::WasiCtx, RuntimeError,
+};
+
 #[allow(dead_code)]
 #[derive(Debug)]
 pub struct Module<'runtime> {
@@ -44,7 +38,10 @@ impl<'runtime> Module<'runtime> {
     ///
     /// If the file does not exist or the file cannot be read, an `RuntimeError::WasmFileFSError` will be returned.
     /// If the wasm file is not a valid wasm file, an `RuntimeError::CompilationError` will be returned.
-    pub fn from_file(runtime: &'runtime Runtime, wasm_file: &Path) -> Result<Self, RuntimeError> {
+    #[cfg(any(test, feature = "std"))]
+    pub fn from_file(runtime: &'runtime Runtime, wasm_file: &std::path::Path) -> Result<Self, RuntimeError> {
+        use std::{fs::File, io::Read};
+
         let name = wasm_file.file_name().unwrap().to_str().unwrap();
         let mut wasm_file = File::open(wasm_file)?;
 
@@ -202,7 +199,7 @@ impl Drop for Module<'_> {
 mod tests {
     use super::*;
     use crate::{helper::cstr_to_string, runtime::Runtime, wasi_context::WasiCtxBuilder};
-    use std::path::PathBuf;
+    use std::path::{Path, PathBuf};
     use wamr_sys::wasm_runtime_get_module_name;
 
     #[test]

src/runtime.rs

@@ -7,7 +7,8 @@
 //! Every process should have only one instance of this runtime by call
 //! `Runtime::new()` or `Runtime::builder().build()` once.
 
-use std::ffi::c_void;
+use alloc::vec::Vec;
+use core::ffi::c_void;
 
 use wamr_sys::{
     mem_alloc_type_t_Alloc_With_Pool, mem_alloc_type_t_Alloc_With_System_Allocator,
@@ -68,15 +69,19 @@ pub struct RuntimeBuilder {
 /// Can't build() until config allocator mode
 impl Default for RuntimeBuilder {
     fn default() -> Self {
-        let args = RuntimeInitArgs::default();
-        RuntimeBuilder {
-            args,
-            host_functions: HostFunctionList::new("host"),
-        }
+        Self::new("host")
     }
 }
 
 impl RuntimeBuilder {
+    /// create a named module runtime builder
+    pub fn new(name: &str) -> Self {
+        Self {
+            args: RuntimeInitArgs::default(),
+            host_functions: HostFunctionList::new(name),
+        }
+    }
+
     /// system allocator mode
     /// allocate memory from system allocator for runtime consumed memory
     pub fn use_system_allocator(mut self) -> RuntimeBuilder {

src/value.rs

@@ -5,6 +5,8 @@
 
 //! a wasm value. Always used as function parameters and results
 
+use alloc::vec::Vec;
+
 #[derive(Debug, PartialEq)]
 pub enum WasmValue {
     Void,
@@ -22,23 +24,23 @@ impl WasmValue {
                 vec![]
             }
             WasmValue::I32(value) => {
-                let in_u32_array = unsafe { std::mem::transmute::<i32, [u32; 1]>(value) };
+                let in_u32_array = unsafe { core::mem::transmute::<i32, [u32; 1]>(value) };
                 vec![in_u32_array[0]]
             }
             WasmValue::I64(value) => {
-                let in_u32_array = unsafe { std::mem::transmute::<i64, [u32; 2]>(value) };
+                let in_u32_array = unsafe { core::mem::transmute::<i64, [u32; 2]>(value) };
                 vec![in_u32_array[0], in_u32_array[1]]
             }
             WasmValue::F32(value) => {
-                let in_u32_array = unsafe { std::mem::transmute::<f32, [u32; 1]>(value) };
+                let in_u32_array = unsafe { core::mem::transmute::<f32, [u32; 1]>(value) };
                 vec![in_u32_array[0]]
             }
             WasmValue::F64(value) => {
-                let in_u32_array = unsafe { std::mem::transmute::<f64, [u32; 2]>(value) };
+                let in_u32_array = unsafe { core::mem::transmute::<f64, [u32; 2]>(value) };
                 vec![in_u32_array[0], in_u32_array[1]]
             }
             WasmValue::V128(value) => {
-                let in_u32_array = unsafe { std::mem::transmute::<i128, [u32; 4]>(value) };
+                let in_u32_array = unsafe { core::mem::transmute::<i128, [u32; 4]>(value) };
                 vec![
                     in_u32_array[0],
                     in_u32_array[1],
@@ -51,27 +53,27 @@ impl WasmValue {
 
     pub fn decode_to_i32(binary: Vec<u32>) -> WasmValue {
         let binary: [u32; 1] = [binary[0]];
-        WasmValue::I32(unsafe { std::mem::transmute::<[u32; 1], i32>(binary) })
+        WasmValue::I32(unsafe { core::mem::transmute::<[u32; 1], i32>(binary) })
     }
 
     pub fn decode_to_f32(binary: Vec<u32>) -> WasmValue {
         let binary: [u32; 1] = [binary[0]];
-        WasmValue::F32(unsafe { std::mem::transmute::<[u32; 1], f32>(binary) })
+        WasmValue::F32(unsafe { core::mem::transmute::<[u32; 1], f32>(binary) })
     }
 
     pub fn decode_to_i64(binary: Vec<u32>) -> WasmValue {
         let binary: [u32; 2] = [binary[0], binary[1]];
-        WasmValue::I64(unsafe { std::mem::transmute::<[u32; 2], i64>(binary) })
+        WasmValue::I64(unsafe { core::mem::transmute::<[u32; 2], i64>(binary) })
     }
 
     pub fn decode_to_f64(binary: Vec<u32>) -> WasmValue {
         let binary: [u32; 2] = [binary[0], binary[1]];
-        WasmValue::F64(unsafe { std::mem::transmute::<[u32; 2], f64>(binary) })
+        WasmValue::F64(unsafe { core::mem::transmute::<[u32; 2], f64>(binary) })
     }
 
     pub fn decode_to_v128(binary: Vec<u32>) -> WasmValue {
         let binary: [u32; 4] = [binary[0], binary[1], binary[2], binary[3]];
-        WasmValue::V128(unsafe { std::mem::transmute::<[u32; 4], i128>(binary) })
+        WasmValue::V128(unsafe { core::mem::transmute::<[u32; 4], i128>(binary) })
     }
 }
 

src/wasi_context.rs

@@ -5,7 +5,8 @@
 
 //! prepare wasi context
 
-use std::{ffi::c_char, ffi::CString, vec::Vec};
+use alloc::{ffi::CString, vec::Vec};
+use core::ffi::c_char;
 
 #[derive(Debug, Default)]
 struct PreOpen {