Add lua emscripten support

Cargo.toml

@@ -60,20 +60,26 @@ ffi = { package = "mlua-sys", version = "0.4.0", path = "mlua-sys" }
 [target.'cfg(unix)'.dependencies]
 libloading = { version = "0.8", optional = true }
 
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+ffi = { package = "mlua-sys", version = "0.4.0", path = "mlua-sys", features = ["vendored"] }
+
 [dev-dependencies]
-rustyline = "12.0"
-criterion = { version = "0.5", features = ["async_tokio"] }
 trybuild = "1.0"
 futures = "0.3.5"
 hyper = { version = "0.14", features = ["client", "server"] }
 reqwest = { version = "0.11", features = ["json"] }
-tokio = { version = "1.0", features = ["full"] }
+tokio = { version = "1.0", features = ["macros", "rt", "time"] }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 maplit = "1.0"
 tempfile = "3"
 static_assertions = "1.0"
 
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
+criterion = { version = "0.5", features = ["async_tokio"] }
+rustyline = "12.0"
+tokio = { version = "1.0", features = ["full"] }
+
 [[bench]]
 name = "benchmark"
 harness = false

examples/async_http_client.rs

@@ -1,3 +1,6 @@
+#[cfg(target_arch = "wasm32")]
+compile_error!("Not available for wasm");
+
 use std::collections::HashMap;
 
 use hyper::body::{Body as HyperBody, HttpBody as _};

examples/async_http_reqwest.rs

@@ -1,6 +1,6 @@
 use mlua::{chunk, ExternalResult, Lua, LuaSerdeExt, Result};
 
-#[tokio::main]
+#[tokio::main(flavor = "current_thread")]
 async fn main() -> Result<()> {
     let lua = Lua::new();
 

examples/async_http_server.rs

@@ -1,3 +1,6 @@
+#[cfg(target_arch = "wasm32")]
+compile_error!("Not available for wasm");
+
 use std::future::Future;
 use std::net::SocketAddr;
 use std::pin::Pin;

examples/async_tcp_server.rs

@@ -1,3 +1,6 @@
+#[cfg(target_arch = "wasm32")]
+compile_error!("Not available for wasm");
+
 use std::io;
 use std::net::SocketAddr;
 use std::rc::Rc;

examples/repl.rs

@@ -1,4 +1,6 @@
 //! This example shows a simple read-evaluate-print-loop (REPL).
+#[cfg(target_arch = "wasm32")]
+compile_error!("Not available for wasm");
 
 use mlua::{Error, Lua, MultiValue};
 use rustyline::DefaultEditor;

mlua-sys/src/lua51/compat.rs

@@ -145,6 +145,12 @@ unsafe fn compat53_pushfuncname(L: *mut lua_State, ar: *mut lua_Debug) {
 // lua ported functions
 //
 
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!()
+}
+
 #[inline(always)]
 pub unsafe fn lua_absindex(L: *mut lua_State, mut idx: c_int) -> c_int {
     if idx < 0 && idx > LUA_REGISTRYINDEX {

mlua-sys/src/lua51/lauxlib.rs

@@ -43,7 +43,7 @@ extern "C-unwind" {
     pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
 
     pub fn luaL_where(L: *mut lua_State, lvl: c_int);
-    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> !;
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> c_int;
 
     pub fn luaL_checkoption(
         L: *mut lua_State,

mlua-sys/src/lua51/lua.rs

@@ -228,7 +228,8 @@ extern "C-unwind" {
 //
 #[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
 extern "C-unwind" {
-    pub fn lua_error(L: *mut lua_State) -> !;
+    #[link_name = "lua_error"]
+    pub fn lua_error_(L: *mut lua_State) -> c_int;
     pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
     pub fn lua_concat(L: *mut lua_State, n: c_int);
     pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;

mlua-sys/src/lua52/compat.rs

@@ -25,6 +25,12 @@ unsafe fn compat53_reverse(L: *mut lua_State, mut a: c_int, mut b: c_int) {
 // lua ported functions
 //
 
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut crate::lua_State) -> ! {
+    crate::lua_error_(L);
+    unreachable!()
+}
+
 pub unsafe fn lua_rotate(L: *mut lua_State, mut idx: c_int, mut n: c_int) {
     idx = lua_absindex(L, idx);
     if n > 0 {

mlua-sys/src/lua52/lauxlib.rs

@@ -49,7 +49,7 @@ extern "C-unwind" {
     pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
 
     pub fn luaL_where(L: *mut lua_State, lvl: c_int);
-    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> !;
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> c_int;
 
     pub fn luaL_checkoption(
         L: *mut lua_State,

mlua-sys/src/lua52/lua.rs

@@ -308,7 +308,8 @@ extern "C-unwind" {
     //
     // Miscellaneous functions
     //
-    pub fn lua_error(L: *mut lua_State) -> !;
+    #[link_name = "lua_error"]
+    pub fn lua_error_(L: *mut lua_State) -> c_int;
     pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
     pub fn lua_concat(L: *mut lua_State, n: c_int);
     pub fn lua_len(L: *mut lua_State, idx: c_int);
@@ -453,7 +454,12 @@ extern "C-unwind" {
     pub fn lua_upvalueid(L: *mut lua_State, fidx: c_int, n: c_int) -> *mut c_void;
     pub fn lua_upvaluejoin(L: *mut lua_State, fidx1: c_int, n1: c_int, fidx2: c_int, n2: c_int);
 
-    pub fn lua_sethook(L: *mut lua_State, func: Option<lua_Hook>, mask: c_int, count: c_int);
+    pub fn lua_sethook(
+        L: *mut lua_State,
+        func: Option<lua_Hook>,
+        mask: c_int,
+        count: c_int,
+    ) -> c_int;
     pub fn lua_gethook(L: *mut lua_State) -> Option<lua_Hook>;
     pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
     pub fn lua_gethookcount(L: *mut lua_State) -> c_int;

mlua-sys/src/lua53/compat.rs

@@ -4,6 +4,12 @@ use std::os::raw::c_int;
 
 use super::lua::*;
 
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!()
+}
+
 #[inline(always)]
 pub unsafe fn lua_resume(
     L: *mut lua_State,

mlua-sys/src/lua53/lua.rs

@@ -314,7 +314,8 @@ extern "C-unwind" {
     //
     // Miscellaneous functions
     //
-    pub fn lua_error(L: *mut lua_State) -> !;
+    #[link_name = "lua_error"]
+    pub fn lua_error_(L: *mut lua_State) -> c_int;
     pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
     pub fn lua_concat(L: *mut lua_State, n: c_int);
     pub fn lua_len(L: *mut lua_State, idx: c_int);

mlua-sys/src/lua54/compat.rs

@@ -0,0 +1,15 @@
+//! MLua compatibility layer for Lua 5.4
+
+use super::lua::*;
+use std::os::raw::c_int;
+
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!()
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize {
+    lua_rawlen_(L, idx) as usize
+}

mlua-sys/src/lua54/lua.rs

@@ -149,7 +149,8 @@ extern "C-unwind" {
     pub fn lua_tointegerx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Integer;
     pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
     pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
-    pub fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize;
+    #[link_name = "lua_rawlen"]
+    pub fn lua_rawlen_(L: *mut lua_State, idx: c_int) -> lua_Unsigned;
     pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
     pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
     pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
@@ -336,7 +337,8 @@ extern "C-unwind" {
     //
     // Miscellaneous functions
     //
-    pub fn lua_error(L: *mut lua_State) -> !;
+    #[link_name = "lua_error"]
+    pub fn lua_error_(L: *mut lua_State) -> c_int;
     pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
     pub fn lua_concat(L: *mut lua_State, n: c_int);
     pub fn lua_len(L: *mut lua_State, idx: c_int);

mlua-sys/src/lua54/mod.rs

@@ -1,9 +1,11 @@
 //! Low level bindings to Lua 5.4.
 
+pub use compat::*;
 pub use lauxlib::*;
 pub use lua::*;
 pub use lualib::*;
 
+pub mod compat;
 pub mod lauxlib;
 pub mod lua;
 pub mod lualib;

tests/chunk.rs

@@ -1,9 +1,12 @@
+#![allow(unused_imports)]
+
 use std::fs;
 use std::io;
 
 use mlua::{Lua, Result};
 
 #[test]
+#[cfg(not(target_arch = "wasm32"))]
 fn test_chunk_path() -> Result<()> {
     let lua = Lua::new();