feat(wasi) Implement WASI

wasmer/config_test.go

@@ -11,7 +11,7 @@ func TestConfig(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -31,7 +31,7 @@ func TestConfig_UseJITEngine(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -55,7 +55,7 @@ func TestConfig_UseNativeEngine(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -75,7 +75,7 @@ func TestConfig_UseCraneliftCompiler(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -99,7 +99,7 @@ func TestConfig_UseLLVMCompiler(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -120,7 +120,7 @@ func TestConfig_JITWithCranelift(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -145,7 +145,7 @@ func TestConfig_JITWithLLVM(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -166,7 +166,7 @@ func TestConfig_NativeWithCranelift(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())
@@ -191,7 +191,7 @@ func TestConfig_NativeWithLLVM(t *testing.T) {
 
 	engine := NewEngineWithConfig(config)
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())

wasmer/engine_test.go

@@ -8,7 +8,7 @@ import (
 
 func testEngine(t *testing.T, engine *Engine) {
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())

wasmer/exports.go

@@ -11,12 +11,14 @@ import (
 type Exports struct {
 	_inner  C.wasm_extern_vec_t
 	exports map[string]*Extern
+	instance *C.wasm_instance_t
 }
 
 func newExports(instance *C.wasm_instance_t, module *Module) *Exports {
 	self := &Exports{}
 	C.wasm_instance_exports(instance, &self._inner)
 
+	runtime.KeepAlive(instance)
 	runtime.SetFinalizer(self, func(exports *Exports) {
 		C.wasm_extern_vec_delete(exports.inner())
 	})
@@ -37,6 +39,7 @@ func newExports(instance *C.wasm_instance_t, module *Module) *Exports {
 	}
 
 	self.exports = exports
+	self.instance = instance
 
 	return self
 }
@@ -98,7 +101,7 @@ func (self *Exports) GetRawFunction(name string) (*Function, error) {
 //       exportedFunc()
 //   }
 //
-func (self *Exports) GetFunction(name string) (func(...interface{}) (interface{}, error), error) {
+func (self *Exports) GetFunction(name string) (NativeFunction, error) {
 	function, err := self.GetRawFunction(name)
 
 	if err != nil {
@@ -164,3 +167,13 @@ func (self *Exports) GetMemory(name string) (*Memory, error) {
 
 	return exports.IntoMemory(), nil
 }
+
+func (self *Exports) GetWasiStartFunction() (NativeFunction, error) {
+	start := C.wasi_get_start_function(self.instance)
+
+	if start == nil {
+		return nil, newErrorWith("WASI start function was not found")
+	}
+
+	return newFunction(start, nil, nil).Native(), nil
+}

wasmer/function.go

@@ -19,11 +19,13 @@ import (
 	"unsafe"
 )
 
+type NativeFunction = func(...interface{}) (interface{}, error)
+
 type Function struct {
 	_inner      *C.wasm_func_t
 	_ownedBy    interface{}
 	environment *FunctionEnvironment
-	lazyNative  func(...interface{}) (interface{}, error)
+	lazyNative  NativeFunction
 }
 
 func newFunction(pointer *C.wasm_func_t, environment *FunctionEnvironment, ownedBy interface{}) *Function {
@@ -181,7 +183,7 @@ func (self *Function) Call(parameters ...interface{}) (interface{}, error) {
 //   nativeFunction = function.Native()
 //   _ = nativeFunction(1, 2, 3)
 //
-func (self *Function) Native() func(...interface{}) (interface{}, error) {
+func (self *Function) Native() NativeFunction {
 	if self.lazyNative != nil {
 		return self.lazyNative
 	}

wasmer/import_object.go

@@ -8,8 +8,7 @@ import (
 )
 
 type ImportObject struct {
-	externs       map[string]map[string]IntoExtern
-	opaqueExterns []IntoExtern
+	externs map[string]map[string]IntoExtern
 }
 
 // NewImportObject instantiates a new empty ImportObject.
@@ -18,21 +17,13 @@ type ImportObject struct {
 //
 func NewImportObject() *ImportObject {
 	return &ImportObject{
-		externs:       make(map[string]map[string]IntoExtern),
-		opaqueExterns: nil,
+		externs: make(map[string]map[string]IntoExtern),
 	}
 }
 
 func (self *ImportObject) intoInner(module *Module) (*C.wasm_extern_vec_t, error) {
 	cExterns := &C.wasm_extern_vec_t{}
 
-	/*
-		// TODO(ivan): review this
-			runtime.SetFinalizer(cExterns, func(cExterns *C.wasm_extern_vec_t) {
-				C.wasm_extern_vec_delete(cExterns)
-			})
-	*/
-
 	var externs []*C.wasm_extern_t
 	var numberOfExterns uint
 
@@ -50,11 +41,6 @@ func (self *ImportObject) intoInner(module *Module) (*C.wasm_extern_vec_t, error
 		numberOfExterns++
 	}
 
-	for _, extern := range self.opaqueExterns {
-		externs = append(externs, extern.IntoExtern().inner())
-		numberOfExterns++
-	}
-
 	if numberOfExterns > 0 {
 		C.wasm_extern_vec_new(cExterns, C.size_t(numberOfExterns), (**C.wasm_extern_t)(unsafe.Pointer(&externs[0])))
 	}
@@ -110,7 +96,3 @@ func (self *ImportObject) Register(namespaceName string, namespace map[string]In
 		}
 	}
 }
-
-func (self *ImportObject) addOpaqueExtern(extern *Extern) {
-	self.opaqueExterns = append(self.opaqueExterns, extern)
-}

wasmer/testdata/wasi.rs

@@ -0,0 +1,54 @@
+// Compiled to Wasm as follows:
+//
+// ```sh
+// $ rustc --target wasm32-wasi -O wasi.rs -o wasi.raw.wasm
+// $ wasm-strip wasi.raw.wasm
+// $ wasm-opt -O4 -Oz wasi.raw.wasm -o wasi.wasm
+// ```
+
+use std::{env, fs};
+
+fn main() {
+    // Arguments
+    {
+        let mut arguments = env::args().collect::<Vec<String>>();
+
+        println!("Found program name: `{}`", arguments[0]);
+
+        arguments = arguments[1..].to_vec();
+        println!(
+            "Found {} arguments: {}",
+            arguments.len(),
+            arguments.join(", ")
+        );
+    }
+
+    // Environment variables
+    {
+        let mut environment_variables = env::vars()
+            .map(|(arg, val)| format!("{}={}", arg, val))
+            .collect::<Vec<String>>();
+        environment_variables.sort();
+
+        println!(
+            "Found {} environment variables: {}",
+            environment_variables.len(),
+            environment_variables.join(", ")
+        );
+    }
+
+    // Directories.
+    {
+        let root = fs::read_dir("/")
+            .unwrap()
+            .map(|e| e.map(|inner| format!("{:?}", inner)))
+            .collect::<Result<Vec<String>, _>>()
+            .unwrap();
+
+        println!(
+            "Found {} preopened directories: {}",
+            root.len(),
+            root.join(", ")
+        );
+    }
+}

wasmer/utils_test.go

@@ -8,9 +8,9 @@ import (
 	"testing"
 )
 
-func testGetBytes() []byte {
+func testGetBytes(moduleFileName string) []byte {
 	_, filename, _, _ := runtime.Caller(0)
-	modulePath := path.Join(path.Dir(filename), "testdata", "tests.wasm")
+	modulePath := path.Join(path.Dir(filename), "testdata", moduleFileName)
 	bytes, _ := ioutil.ReadFile(modulePath)
 
 	return bytes
@@ -19,7 +19,7 @@ func testGetBytes() []byte {
 func testGetInstance(t *testing.T) *Instance {
 	engine := NewEngine()
 	store := NewStore(engine)
-	module, err := NewModule(store, testGetBytes())
+	module, err := NewModule(store, testGetBytes("tests.wasm"))
 	assert.NoError(t, err)
 
 	instance, err := NewInstance(module, NewImportObject())