Merge #299

299: Support for the WASI ABI. r=xmclark a=lachlansneff

part of #297 

Co-authored-by: Lachlan Sneff <[email protected]>
Co-authored-by: Mark McCaskey <[email protected]>
Co-authored-by: bors[bot] <bors[bot]@users.noreply.github.com>
Co-authored-by: Mark McCaskey <[email protected]>

Author: 4 people

Diff for: Cargo.lock

@@ -30,9 +30,10 @@ wasmer-runtime-abi = { path = "lib/runtime-abi", optional = true }
 wasmer-runtime-core = { path = "lib/runtime-core" }
 wasmer-emscripten = { path = "lib/emscripten" }
 wasmer-llvm-backend = { path = "lib/llvm-backend", optional = true }
+wasmer-wasi = { path = "lib/wasi", optional = true }
 
 [workspace]
-members = ["lib/clif-backend", "lib/dynasm-backend", "lib/runtime", "lib/runtime-abi", "lib/runtime-core", "lib/emscripten", "lib/spectests", "lib/win-exception-handler", "lib/runtime-c-api", "lib/llvm-backend"]
+members = ["lib/clif-backend", "lib/dynasm-backend", "lib/runtime", "lib/runtime-abi", "lib/runtime-core", "lib/emscripten", "lib/spectests", "lib/win-exception-handler", "lib/runtime-c-api", "lib/llvm-backend", "lib/wasi"]
 
 [build-dependencies]
 wabt = "0.7.2"
@@ -45,4 +46,5 @@ debug = ["wasmer-clif-backend/debug", "wasmer-runtime-core/debug"]
 fast-tests = []
 llvm = ["wasmer-llvm-backend"]
 dynasm = ["wasmer-dynasm-backend"]
+wasi = ["wasmer-wasi"]
 vfs = ["wasmer-runtime-abi"]

Diff for: Cargo.toml

@@ -119,7 +119,6 @@ impl std::error::Error for LinkError {}
 /// The main way to do this is `Instance.call`.
 ///
 /// Comparing two `RuntimeError`s always evaluates to false.
-#[derive(Debug)]
 pub enum RuntimeError {
     Trap { msg: Box<str> },
     Exception { data: Box<[Value]> },
@@ -141,11 +140,27 @@ impl std::fmt::Display for RuntimeError {
             RuntimeError::Exception { ref data } => {
                 write!(f, "Uncaught WebAssembly exception: {:?}", data)
             }
-            RuntimeError::Panic { data: _ } => write!(f, "User-defined \"panic\""),
+            RuntimeError::Panic { data } => {
+                let msg = if let Some(s) = data.downcast_ref::<String>() {
+                    s
+                } else if let Some(s) = data.downcast_ref::<&str>() {
+                    s
+                } else {
+                    "user-defined, opaque"
+                };
+
+                write!(f, "{}", msg)
+            }
         }
     }
 }
 
+impl std::fmt::Debug for RuntimeError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}", self)
+    }
+}
+
 impl std::error::Error for RuntimeError {}
 
 /// This error type is produced by resolving a wasm function
@@ -197,7 +212,6 @@ impl std::error::Error for ResolveError {}
 /// be the `CallError::Runtime(RuntimeError)` variant.
 ///
 /// Comparing two `CallError`s always evaluates to false.
-#[derive(Debug)]
 pub enum CallError {
     Resolve(ResolveError),
     Runtime(RuntimeError),
@@ -218,6 +232,15 @@ impl std::fmt::Display for CallError {
     }
 }
 
+impl std::fmt::Debug for CallError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            CallError::Resolve(resolve_err) => write!(f, "ResolveError: {:?}", resolve_err),
+            CallError::Runtime(runtime_err) => write!(f, "RuntimeError: {:?}", runtime_err),
+        }
+    }
+}
+
 impl std::error::Error for CallError {}
 
 /// This error type is produced when creating something,

Diff for: lib/runtime-core/src/error.rs

@@ -3,6 +3,7 @@ use hashbrown::{hash_map::Entry, HashMap};
 use std::collections::VecDeque;
 use std::{
     cell::{Ref, RefCell},
+    ffi::c_void,
     rc::Rc,
 };
 
@@ -45,16 +46,32 @@ impl IsExport for Export {
 /// ```
 pub struct ImportObject {
     map: Rc<RefCell<HashMap<String, Box<dyn LikeNamespace>>>>,
+    state_creator: Option<Rc<Fn() -> (*mut c_void, fn(*mut c_void))>>,
 }
 
 impl ImportObject {
     /// Create a new `ImportObject`.  
     pub fn new() -> Self {
         Self {
             map: Rc::new(RefCell::new(HashMap::new())),
+            state_creator: None,
         }
     }
 
+    pub fn new_with_data<F>(state_creator: F) -> Self
+    where
+        F: Fn() -> (*mut c_void, fn(*mut c_void)) + 'static,
+    {
+        Self {
+            map: Rc::new(RefCell::new(HashMap::new())),
+            state_creator: Some(Rc::new(state_creator)),
+        }
+    }
+
+    pub(crate) fn call_state_creator(&self) -> Option<(*mut c_void, fn(*mut c_void))> {
+        self.state_creator.as_ref().map(|state_gen| state_gen())
+    }
+
     /// Register anything that implements `LikeNamespace` as a namespace.
     ///
     /// # Usage:
@@ -98,6 +115,7 @@ impl ImportObject {
     pub fn clone_ref(&self) -> Self {
         Self {
             map: Rc::clone(&self.map),
+            state_creator: self.state_creator.clone(),
         }
     }
 

Diff for: lib/runtime-core/src/import.rs

@@ -63,7 +63,16 @@ impl Instance {
         // Initialize the vm::Ctx in-place after the backing
         // has been boxed.
         unsafe {
-            *inner.vmctx = vm::Ctx::new(&mut inner.backing, &mut inner.import_backing, &module)
+            *inner.vmctx = match imports.call_state_creator() {
+                Some((data, dtor)) => vm::Ctx::new_with_data(
+                    &mut inner.backing,
+                    &mut inner.import_backing,
+                    &module,
+                    data,
+                    dtor,
+                ),
+                None => vm::Ctx::new(&mut inner.backing, &mut inner.import_backing, &module),
+            };
         };
 
         let instance = Instance {

Diff for: lib/runtime-core/src/instance.rs

@@ -38,6 +38,13 @@ macro_rules! func {
 ///     },
 /// };
 ///
+/// let imports_with_state = imports! {
+///     || (0 as _, |_a| {}),
+///     "env" => {
+///         "foo" => func!(foo),
+///     },
+/// };
+///
 /// fn foo(_: &mut Ctx, n: i32) -> i32 {
 ///     n
 /// }
@@ -57,6 +64,21 @@ macro_rules! imports {
             import_object.register($ns_name, ns);
         })*
 
+        import_object
+    }};
+    ($state_gen:expr, $( $ns_name:expr => $ns:tt, )* ) => {{
+        use $crate::{
+            import::{ImportObject, Namespace},
+        };
+
+        let mut import_object = ImportObject::new_with_data($state_gen);
+
+        $({
+            let ns = $crate::__imports_internal!($ns);
+
+            import_object.register($ns_name, ns);
+        })*
+
         import_object
     }};
 }

Diff for: lib/runtime-core/src/macros.rs

@@ -77,6 +77,19 @@ where
 {
     const TYPE: Type;
 }
+
+unsafe impl WasmExternType for i8 {
+    const TYPE: Type = Type::I32;
+}
+unsafe impl WasmExternType for u8 {
+    const TYPE: Type = Type::I32;
+}
+unsafe impl WasmExternType for i16 {
+    const TYPE: Type = Type::I32;
+}
+unsafe impl WasmExternType for u16 {
+    const TYPE: Type = Type::I32;
+}
 unsafe impl WasmExternType for i32 {
     const TYPE: Type = Type::I32;
 }
@@ -113,34 +126,15 @@ unsafe impl WasmExternType for f64 {
 //     fn swap(&self, other: Self::Primitive) -> Self::Primitive;
 // }
 
-pub enum ValueError {
-    BufferTooSmall,
-}
-
-pub trait ValueType: Copy
+pub unsafe trait ValueType: Copy
 where
     Self: Sized,
 {
-    fn into_le(self, buffer: &mut [u8]);
-    fn from_le(buffer: &[u8]) -> Result<Self, ValueError>;
 }
 
 macro_rules! convert_value_impl {
     ($t:ty) => {
-        impl ValueType for $t {
-            fn into_le(self, buffer: &mut [u8]) {
-                buffer[..mem::size_of::<Self>()].copy_from_slice(&self.to_le_bytes());
-            }
-            fn from_le(buffer: &[u8]) -> Result<Self, ValueError> {
-                if buffer.len() >= mem::size_of::<Self>() {
-                    let mut array = [0u8; mem::size_of::<Self>()];
-                    array.copy_from_slice(&buffer[..mem::size_of::<Self>()]);
-                    Ok(Self::from_le_bytes(array))
-                } else {
-                    Err(ValueError::BufferTooSmall)
-                }
-            }
-        }
+        unsafe impl ValueType for $t {}
     };
     ( $($t:ty),* ) => {
         $(
@@ -149,25 +143,7 @@ macro_rules! convert_value_impl {
     };
 }
 
-convert_value_impl!(u8, i8, u16, i16, u32, i32, u64, i64);
-
-impl ValueType for f32 {
-    fn into_le(self, buffer: &mut [u8]) {
-        self.to_bits().into_le(buffer);
-    }
-    fn from_le(buffer: &[u8]) -> Result<Self, ValueError> {
-        Ok(f32::from_bits(<u32 as ValueType>::from_le(buffer)?))
-    }
-}
-
-impl ValueType for f64 {
-    fn into_le(self, buffer: &mut [u8]) {
-        self.to_bits().into_le(buffer);
-    }
-    fn from_le(buffer: &[u8]) -> Result<Self, ValueError> {
-        Ok(f64::from_bits(<u64 as ValueType>::from_le(buffer)?))
-    }
-}
+convert_value_impl!(u8, i8, u16, i16, u32, i32, u64, i64, f32, f64);
 
 #[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ElementType {

Diff for: lib/runtime-core/src/types.rs

@@ -25,7 +25,7 @@ pub struct Ctx {
     module: *const ModuleInner,
 
     pub data: *mut c_void,
-    pub data_finalizer: Option<extern "C" fn(data: *mut c_void)>,
+    pub data_finalizer: Option<fn(data: *mut c_void)>,
 }
 
 /// The internal context of the currently running WebAssembly instance.
@@ -100,7 +100,7 @@ impl Ctx {
         import_backing: &mut ImportBacking,
         module: &ModuleInner,
         data: *mut c_void,
-        data_finalizer: extern "C" fn(*mut c_void),
+        data_finalizer: fn(*mut c_void),
     ) -> Self {
         Self {
             internal: InternalCtx {
@@ -481,7 +481,7 @@ mod vm_ctx_tests {
         str: String,
     }
 
-    extern "C" fn test_data_finalizer(data: *mut c_void) {
+    fn test_data_finalizer(data: *mut c_void) {
         let test_data: &mut TestData = unsafe { &mut *(data as *mut TestData) };
         assert_eq!(test_data.x, 10);
         assert_eq!(test_data.y, true);

Diff for: lib/runtime-core/src/vm.rs

@@ -0,0 +1,22 @@
+[package]
+name = "wasmer-wasi"
+version = "0.2.1"
+license = "MIT"
+authors = ["The Wasmer Engineering Team <[email protected]>"]
+repository = "https://github.com/wasmerio/wasmer"
+edition = "2018"
+
+[dependencies]
+wasmer-runtime-core = { path = "../runtime-core", version = "0.2.1" }
+libc = "0.2.50"
+rand = "0.6.5"
+# wasmer-runtime-abi = { path = "../runtime-abi" }
+hashbrown = "0.1.8"
+generational-arena = "0.2.2"
+log = "0.4.6"
+byteorder = "1.3.1"
+
+[dependencies.zbox]
+git = "https://github.com/wasmerio/zbox"
+branch = "bundle-libsodium"
+features = ["libsodium-bundled"]